JP5318274B1 - Screw tightening tool with marking function - Google Patents

Abstract

To provide a screw tightening tool capable of reliably marking a screw head after detecting that a screw tightening torque has reached a predetermined value.
An impact wrench (1) has a socket part (10) at the tip of an impact wrench body (2). The socket part 10 is configured so that the socket main body part 11 and the socket front end part 20 can be separated via a connecting metal fitting 17 and a rubber band 18 that can be prevented from being detached. When the tightening torque reaches a predetermined value, the second air circuit 30 configured separately from the first air circuit 30B that rotationally drives the socket portion 10 is operated to move the marking portion 13 toward the screw head. Mark.
[Selection] Figure 1

Description

  The present invention relates to a screw tightening tool with a marking function capable of automatically performing a visible marking on the head of a screw in order to confirm whether or not the screw has been securely tightened with a predetermined torque. Examples of the screw tightening tool of the present invention include an impact wrench, an impact driver, a torque wrench, a socket wrench, and the like.

  Conventionally, when a screw is tightened with a screw tightening tool such as an impact wrench, marking has been performed on the head of the screw to confirm whether the screw tightening is performed within a predetermined torque. For example, the marking tool is moved forward by a solenoid provided at the rear part in the electric tightening machine, and the bolt head is marked to determine whether it is tightened within a normal torque at a glance (see Patent Document 1). ) And an air impact wrench equipped with a shut-off valve, and the ink pressure inside the socket is moved forward using the back pressure when the bolts are tightened. A fixed amount of ink is supplied at the tip. When marking the bolt head with the stamped sponge (see Patent Document 2) and a marking tool for attaching ink to the tip surface of the bolt tip is provided at the bottom of the socket, and the bolt head is inserted into the socket tip In addition, there are known ones in which a mark is attached by a marking shaft soaked with ink (see Patent Document 3, etc.).

Japanese Patent Laid-Open No. 10-156745 JP 2004-268231 A JP-A-9-1472

  However, in Patent Document 1, since a solenoid is integrally formed at the rear part of the electric tightening machine, a through hole is provided at the center of the planetary gear mechanism, and a projecting pin is inserted to advance and retract, the structure is complicated. The cost was high. Further, since ink is not replenished, ink cannot be replenished when ink is insufficient. No measures for ink dripping or replenishment are disclosed.

  Further, Patent Document 2 discloses a configuration in which a trigger is manually operated and an ink cartridge is integrally advanced with a marking tool by using back pressure of air to be printed on a bolt head. The back pressure of the air is generated by the air taken out from the output port by closing the shut-off valve when the bolt tightening torque reaches a predetermined value. Since the pressure of the air that tightens the bolt and the air that advances the marking tool are in the same air circuit, when the bolt tightening force is adjusted sequentially, the driving pressure that advances the marking tool will change, and the density of the marking This will affect the marking itself, such as durability and durability. In addition, even if the ink is insufficient, the ink cannot be replenished. For this reason, it has been troublesome to replace the ink cartridge by removing the screw.

  Furthermore, in Patent Document 3, since all the bolts set in the socket are marked regardless of the tightening torque, it is difficult to confirm whether or not the bolts are securely tightened.

  The present invention solves the above-mentioned problems, and when a screw is tightened, when the screw tightening torque reaches a predetermined value, the head of the screw can be reliably marked, and the marking can be performed instantaneously with an easy configuration. An object of the present invention is to provide a screw tightening tool with a marking function capable of performing the above.

The screw tightening tool with a marking function according to the present invention is configured as follows. That is,
According to the first aspect of the present invention, there is provided a screw tightening tool main body and a screw head rotatably mounted on and tightened to an output shaft of the screw tightening tool main body at one end and the screw head at the other end. And a socket portion having marking means that can be applied to the head, and by attaching ink to the head of the screw to be fastened by the marking means, the screw is fastened with a predetermined torque. A screw tightening tool with a marking function for confirming that the marking means comprises a mark core for attaching the ink to the head of the screw and a marking container body for replenishing the mark core with ink. wherein the air supply means for supplying compressed air along the axial direction of the socket portion is configured to slidably source of the socket portion, holds the marking container body The socket main body and the socket front end connected to the socket main body are configured to be separable, and the socket main body and the socket front end are connected to each other by connecting means formed so as to be prevented from coming off. The socket body portion has a spline shaft in which spline protrusions and spline groove portions are alternately formed at a tip portion of the socket body portion, and the spline is formed at a portion of the socket tip portion facing the socket body portion. An air circuit in which a spline hole to be fitted to the shaft is formed, the socket main body portion and the socket tip end portion are connected by a spline mechanism, and the air supply means is disposed separately from the driving means for rotating the socket portion. And a solenoid valve that opens after the screw tightening torque reaches a predetermined torque and rotation of the socket portion is stopped. The valve is characterized in that is controlled to be held in a predetermined time open state.

  According to this, when the screw tightening torque reaches a predetermined torque, the marking means can apply the ink to the head of the screw. At this time, since the driving pressure for moving the marking means forward is an air circuit installed separately from the driving means for rotating the socket portion, even if the tightening force of the screw in the driving means is adjusted, it is affected. Instead, the head of the screw can be marked. For example, even if the driving means has the same air source as the air circuit and the pressure of the compressed air is adjusted to fasten the screw, the screw head can be marked without being affected by it. . In addition, since the open state of the electromagnetic valve can be maintained for a predetermined time, the marking means can be reliably moved forward.

  Note that holding the electromagnetic valve in the open state for a predetermined time is performed by an operation signal from the control device or by releasing a manual operation button, so that the tightening torque of the screw is predetermined. It is not limited to the air pressure to sense that the inside has been reached. Therefore, the screw tightening tool may be pneumatic, electric, or manual.

  According to this, since the socket portion is configured to be separable into the socket main body portion and the socket tip portion, the marking means as a consumable item disposed in the socket portion can be easily replaced. In addition, since the socket body and the socket tip are connected by a connecting means that can be prevented from being detached, when the socket body and the socket tip are connected, the once-connected socket is simple. Is not broken down.

  According to this, since the socket main body part and the socket front end part are connected by a spline mechanism, when disassembling the socket front end part and the socket main body part, the retaining element is released, and the axial direction When the screw tightening operation is performed, the rotational force of the socket body can be easily transmitted to the socket tip by being connected by a spline mechanism.

In the invention, it is preferable that the connection means includes a connection fitting formed in a ring shape and disposed between the socket main body portion and the socket front end portion, and the spline groove formed in the socket main body portion. It is possible to connect the socket main body part and the socket tip part with an inner protrusion part that can be engaged and an outer protrusion part that can be engaged with a groove formed on the inner peripheral surface of the base part on the socket tip part side. It is characterized by being formed.

  According to this, the said connection means is provided with the connection metal fitting. Since the connecting metal fitting has an inner protrusion that engages with the socket main body and an outer protrusion that engages with the socket front end, the socket main body and the socket front end are engaged with each other. The socket body portion and the socket tip portion can be connected to each other by a single member, and the connecting means can be configured at a low cost.

The present invention further includes a rubber band that externally fits the connection fitting, and the rubber band includes a first cutout portion formed in the connection fitting and a second cutout portion formed in the socket body portion. And a positioning projection that engages with the connector, and is disposed so as to be externally fitted to the connecting metal fitting.

  According to this, the connecting means includes a rubber band, and the rubber band can be positioned and held at a position where the socket main body portion and the socket front end portion are prevented from coming off. That is, by engaging the protrusions for positioning the rubber band with the respective cutout holes formed in the socket main body part and the connecting metal fitting, the socket main body part and the socket tip part in the drop-off prevention position Can be fixed in position. At this time, if an elastic rubber band is previously attached to the socket body before connecting the socket body and the socket tip, the positioning operation can be performed more easily.

Further, the present invention is characterized in that a ring-shaped magnet for preventing a bolt from falling off is disposed on an inner peripheral surface of the socket front end facing the screw head.

  According to this, since the screw inserted into the socket portion can be attracted by a magnet, the screw is not dropped off while inserting the screw or while the inserted screw is held in that position, and reliably It is possible to perform screw insertion work and screw tightening work.

It is a partial sectional view showing an impact wrench of an embodiment of the present invention. It is AA sectional drawing in FIG. It is BB sectional drawing in FIG. It is CC sectional drawing in FIG. It is EE sectional drawing in FIG. It is FF sectional drawing in FIG. It is a disassembled perspective view which shows the positional relationship of a connection metal fitting. It is a perspective view which shows a rubber band. It is a disassembled perspective view which shows the state facing the socket front-end | tip part in the state which mounted | wore the socket main-body part with the connection metal fitting. It is a perspective view which shows the connection state of a socket main-body part and a socket front-end | tip part. It is sectional drawing which shows the detail of a socket front-end | tip part. It is an air piping figure at the time of using an air-type impact wrench. It is an effect | action figure which shows the state before a marking body moves forward. It is an effect | action figure which shows the state after a marking body moves forward. It is a perspective view which shows the connection state of another form of a socket main-body part and a socket front-end | tip part. It is a perspective view which shows the connection state of another form of a socket main-body part and a socket front-end | tip part. It is a perspective view which shows the connection state of another form of a socket main-body part and a socket front-end | tip part. It is a front view which shows the connection state of another form of a socket main-body part and a socket front-end | tip part. It is GG sectional drawing in FIG.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of a screw tightening tool with a marking function of the present invention will be described with reference to the drawings.

  In the following description, a tightening tool used for the screw tightening tool with a marking function of the embodiment will be described with an air impact wrench 1. FIG. 1 is a partial cross-sectional view in which a socket portion 10 is attached to the tip of an impact wrench body 2. FIGS. 2 to 6 are cross-sectional views taken along lines AA, BB, and CC in FIG. , EE cross section and FF cross section are shown. In the description, the direction in which the socket portion 10 attached to the impact wrench body 2 is disposed is referred to as the front side or the front end side, and the impact wrench body 2 side with respect to the socket portion 10 is referred to as the rear side or the base portion side.

  The socket part 10 is configured to be separable into a socket body part 11 fitted to the output angle shaft 3 of the impact wrench body 2 and a socket tip part 20 attached to the tip of the socket body part 11. .

  The socket body 11 is composed of a spline shaft 111 and a body 112 in order from the front end side to the base side, and is a marking that houses the marking portion 13 from the inside of the spline shaft 111 to the inside of the body 112. A part storage part 113 is formed. An air passage 114 is formed in the marking portion storage portion 113 in the body portion 112 at a position separated rearward from the marking portion storage portion 113. In the rear end side base portion of the body portion 112, a square hole 115 that is engaged with the output angular shaft 3 of the impact wrench main body 2 is formed from the rear end face 116 of the socket main body portion 11 toward the front end side. Note that the body portion 112 and the output angular shaft 3 are coupled by a pin 8. The pin 8 is disposed in the body portion 112 by a pin retaining member 9 that fits into a concave groove formed on the rear outer peripheral surface of the body portion 112.

  The marking unit 13 is disposed on the bolt head side to be mounted and marked on the bolt head, and the marking container body 15 is disposed on the base side of the socket body unit 11 and is filled with the ink absorber 151. And.

  The socket front end portion 20 is formed in a stepped cylindrical shape having a large diameter portion 21, a taper portion 22, and a small diameter portion 23 from the rear end side toward the front end side, and the large diameter portion 21 is associated with the spline shaft portion 111. A spline hole 211 is formed. The taper portion 22 is formed with a spring accommodating hole 221 that is smaller in diameter than the spline hole 211 and accommodates the compression coil spring 16. The small-diameter portion 23 is formed with a mark core guide hole 231 having a smaller diameter than the spring housing hole 221. The mark core guide hole 231 is formed so as to penetrate the front end surface of the socket front end portion 20. Further, a bolt head insertion hole 24 that fits into the bolt head from the tip surface of the socket tip portion 20 toward the base portion side is formed. In a state where no bolt is inserted, a lid 42 for closing the mark core guide hole 231 is attached to the distal end surface of the socket distal end portion 20.

  In the embodiment, the mark core 14 is made of an oil-based marker (trade name “Drying Pen (registered trademark)” manufactured by Shachihata Co., Ltd.) in which a special ink film is formed on the surface of the mark core 14 to suppress ink evaporation. Adopted. The tip of the mark core 14 is formed in a protruding shape, and the tip side protruding portion 141 is slidably disposed with the marking container body 15 in the mark core guide hole 231 so as to face the bolt head to be inserted. Yes. The mark core 14 is fitted into the compression coil spring 16 in the spring housing hole 221. The mark core 14 and the marking container main body 15 are connected to each other via a retaining ring 19 disposed in the marking portion storage portion 113. The mark core 14 is not limited to the above-mentioned trade name “Dry Pen (registered trademark)” manufactured by Shachihata Corporation.

  The air passage 114 formed in the socket main body 11 has an axial passage 114a formed along an axial center connected to the base end of the marking portion storage portion 113, and an axial passage connected to one end of the axial passage 114a. A through-passage 114b penetrating in a radial direction in a direction perpendicular to the central passage 114a, and an outer-peripheral passage 114c that is formed in a groove shape over the entire outer peripheral surface of the socket body 11 and is in contact with both ends of the through-passage 114b. ing. One of the through passages 114b is connected to the second air circuit 30 outside the socket body 11 through an air passage 283 of the socket portion side arm holder 28 described later.

  The rotating socket portion 10 is connected to the non-rotating impact wrench body 2 via a rotation stop arm 26. The anti-rotation arm holder 27 and the socket part side arm holder 28 attached to the front end portion 5 of the impact wrench main body 2 are sandwiched between the anti-rotation arms 26 having a square bar shape.

  As shown in FIGS. 1 and 5, the socket side arm holder 28 is prevented from rotating on one piece of a rectangular tubular body 281 (see FIG. 5) and a rectangular tubular body 281 that are externally fitted to the body 112 of the socket main body 11. A holding groove 282 (see FIG. 5) for holding the arm 26 is formed. Since the rectangular tubular body 281 is externally fitted to the trunk portion 112 across the air passage 114 of the trunk portion 112, the air passage 283 is provided in a piece opposite to the holding groove 282 with respect to the axial center of the rectangular tubular body 281. (See FIG. 1). In addition, seal grooves 284 (see FIG. 1) are formed at two positions apart on the inner peripheral surface of the rectangular tubular body 281 and O-rings 29 (see FIG. 1) are mounted respectively. An O-ring 291 that is held in the body portion 112 and fitted to the outer peripheral surface of the marking portion 13 is also mounted at the center portion of the marking portion storage portion 113 in the body portion 112.

  As shown in FIGS. 1 and 6, the anti-rotation arm holder 27 includes an annular part 271 (see FIG. 6) that fits into the main body tip 5 of the impact wrench body 2 and a part of the annular part 271. A protrusion 272 (see FIG. 6) that protrudes from 271 and an opening holding part 273 (see FIG. 6) that sandwich and hold the square-bar-shaped anti-rotation arm 26 in the protrusion 272 are formed. The annular portion 271 is fixed to the main body distal end portion 5 by being screwed to the main body distal end portion 5 (see FIG. 6).

  The second air circuit 30 disposed outside the socket body 11 includes an air source 31, a regulator 32A connected to the air source 31, an electromagnetic valve 33 connected to the regulator 32A, and an electromagnetic valve 33. A timer 34 for setting an opening time, a control device 35 for detecting a tightening torque of a screw within a predetermined range and outputting an operation signal to the timer 34, and a flow rate adjusting valve 36 connected to the electromagnetic valve 33 for adjusting the flow rate of air. And. The air passage 283 of the socket side arm holder 28 is connected to the flow rate adjusting valve 36 via an air hose (not shown).

  The impact wrench 1 is connected to the first air circuit 30B from the same air source 31 as the second air circuit 30 via a regulator 32B installed separately from the regulator 32A. The pressure of air is adjusted by 30B, and the socket part 10 is rotationally driven.

  Next, the connection between the socket body 11 and the socket tip 20 via the connection fitting 17 and the rubber band 18 will be described in detail.

  As shown in FIGS. 2 to 4 and 7, a spline shaft 111 is formed at the front end of the socket body 11 by alternately having spline protrusions 111 a and spline grooves 111 b. A cutout portion 112 a is formed on the outer peripheral portion of the front end of the body portion 112 from the front end surface of the body portion 112 toward the base portion. In FIG. 7, the rotation position is shifted by 30 ° with respect to FIGS.

  The socket front end portion 20 is formed so that a spline hole 211 formed in the large diameter portion 21 can be engaged with the spline shaft portion 111, and is at the rear end side of the spline hole 211 and at the rear end portion of the socket front end portion 20. The three projections 201 projecting inward are formed with the window 202 in between.

  The connection fitting 17 is formed in a ring shape covering the rear outer peripheral surface of the spline shaft portion 111 and is disposed between the socket main body portion 11 and the socket front end portion 20. Three inner projections 171 that pass through the spline groove 111b are formed, and three outer projections 172 that pass through the window 202 of the socket tip 20 are formed on the socket tip side. Further, on the body 112 side of the socket main body 11 on which the inner protrusion 171 is formed, one notch 173 is provided between the two inner protrusions 171 and 171, and the socket main body 11 side end surface of the connecting bracket 17. To the socket tip 20 side.

  As shown in FIG. 8, the rubber band 18 is formed in a ring shape with an elastic rubber material. The width of the rubber band 18 is formed so as to straddle the notch 112a of the socket main body 11 and the notch 173 of the coupling metal 17, and protrudes in the axial direction over the entire width at one place on the inner peripheral surface. An engaging protrusion 181 is formed to be engageable with each of the notches 112a and 173.

  As shown in FIG. 9, the socket front end portion 20 moves toward the connection fitting 17 fitted in front of the body portion 112 of the socket main body portion 11, and the connection fitting 17 is inserted into the socket front end portion 20. When the outer protrusion 172 of the connection fitting 17 passes through the window 202 of the socket tip 20, the connection fitting 17 is rotated so that the outer protrusion 172 of the connection fitting 17 becomes the window of the socket tip 20. It is located on the back side of 202. On the other hand, as shown in FIG. 10, after the notch part 173 of the connecting metal fitting 17 and the notch part 112a formed in the body part 112 of the socket main body part 11 are matched by rotating the connecting metal fitting 17, The rubber band 18 attached to the body part 112 of the part 11 is moved to the connecting bracket 17 side. And the socket main-body part 11 and the socket front-end | tip part 20 are connected in the retaining state by engaging with each notch part 112a, 173 by the engagement protrusion part 181 (refer FIG. 8) of the rubber band 18. FIG. 9 to 10 are drawn by shifting the rotational position by 30 ° with respect to the cross-sectional views of FIGS. 1 to 4 in order to clarify the notch 112a of the socket main body 11 and the notch 173 of the connecting metal member 17. Yes.

  As shown in FIG. 11, a ring-shaped magnet 41 is mounted in the mark core guide hole 231 behind the bolt head insertion hole 24 at the tip of the socket tip 20. By disposing the magnet 41, the bolt B inserted into the bolt head insertion hole 24 can be prevented from falling off.

  Next, the operation of the impact wrench 1 configured as described above will be described.

  In this description, the impact wrench 1 will be described in a form driven by an air type. First, as shown in FIG. 9 and FIG. 10, with the rubber band 18 fitted into the distal end side of the body portion 112 of the socket body portion 11, the connecting metal fitting 17 is connected to the notch portion 112 a of the body portion 112 of the socket body portion 11. Is engaged with the spline shaft portion 111 so that the cut-out portion 173 of the connection fitting 17 is aligned. Then, the outer protrusion 172 of the coupling metal 17 is inserted through the window 202 of the socket tip 20, and the outer protrusion 172 is rotated with respect to the socket tip 20 so as to reach the retaining position. As a result, the socket body 11 and the socket tip 20 are prevented from coming off and assembled together.

  In this state, the bolt B to be tightened is inserted into the bolt head insertion hole 24 of the socket tip 20. Since the bolt B is attracted and held by the magnet 41 embedded in the mark core guide hole 231, it does not fall out of the socket part 10. As shown in FIG. 12, the impact wrench 1 is an air driven type. By manually operating the trigger 7 of the impact wrench body 2, the socket portion 10 is rotated and the bolt B is tightened. The driving pressure for tightening the bolt B is supplied into the impact wrench main body 2 as air supplied from the air source 31 becomes compressed air whose pressure is adjusted by the regulator 32B in the first air circuit 30B. At this time, the socket portion 10 is prevented from shaking by the anti-rotation arm 26 that connects the main body tip portion 5 of the impact wrench main body 2 that is not rotating and the body portion 112 of the socket main body portion 11, and the bolt B is in a stable state. Tightened.

  When the bolt B inserted into the socket tip 20 is completely tightened with a predetermined torque, the rotation of the socket 10 is stopped, and the air discharged from the impact wrench main body 2 is discharged when a shutoff valve (not shown) is shut off. It is discharged for a moment. A part of the exhausted air is supplied to the second air circuit 30. The shut-off valve is connected to an air relay 37 that converts air pressure into electricity. By using the back pressure of the air at the time of shut-off, the air flows into the aerodynamic relay 37, so that the control device 35 recognizes that the bolt B has been completed with a predetermined torque. The control device 35 commands the solenoid valve 33 to be opened for a predetermined time via the timer 34.

  On the other hand, the compressed air whose pressure is adjusted by the regulator 32A flows from the air source 31 to the electromagnetic valve 33 in the second air circuit 30. By opening the electromagnetic valve 33, the compressed air whose pressure is adjusted is connected to the socket. The flow rate is adjusted by the flow rate adjustment valve 36 from the second air circuit 30 arranged outside the portion 10 and flows into the air passage 114 in the socket body 11.

  As shown in FIG. 13, in the state where the bolt B is tightened by the impact wrench 1, the compressed air whose pressure is adjusted from the air source 31 through the regulator 32A is closed by the socket body portion. 11 air passage 114 does not flow. Therefore, the mark core 14 is biased by the compression coil spring 16 and is located away from the head of the bolt B, and no mark is written on the head of the bolt B.

  As shown in FIG. 14, when the tightening torque of the bolt B reaches a predetermined value, the shut-off valve is operated, the air motor (not shown) of the impact wrench 1 is stopped, and the rotation of the socket portion 10 is stopped. As described above, the back pressure of the air acts on the static relay 37, and a signal indicating that the bolt B has been tightened is input to the control device 35 to open the electromagnetic valve 33. At the same time, the opening time of the electromagnetic valve 33 is set from the timer 34 to which the operation signal from the control device 35 is input.

  The compressed air flowing from the electromagnetic valve 33 is adjusted in flow rate by the flow rate adjusting valve 36 and flows from the air passage 283 of the socket portion side arm holder 28 into the through passage 114 b of the socket main body portion 11. The compressed air that has flowed into the through passage 114b flows into the axial passage 114a, and moves the marking portion 13 against the volt B side against the urging force of the compression coil spring 16. The mark core 14 of the marking portion 13 is also moved integrally to the bolt B side, and marking is performed by attaching ink to the head of the bolt B.

  When a predetermined time set by the timer 34 elapses, the electromagnetic valve 33 is closed and the compressed air is discharged to the outside. Therefore, the mark core 14 moves together with the marking container body 15 in the direction away from the bolt B by the urging force of the compression coil spring 16.

  Therefore, in the embodiment, the compressed air pressure for marking the head of the bolt B is regulated by the regulator 32A and the flow rate adjusting valve 36 separately from the driving pressure by the first air circuit 30B that rotates the socket portion 10 of the impact wrench 1. Therefore, even if the driving pressure for rotating the socket portion 10 of the impact wrench 1 is sequentially adjusted by the regulator 32B, the mark core 14 moving forward by the driving pressure by the second air circuit 30 is affected. Instead, the pressing force of the mark core 14 against the bolt B can be adjusted. Therefore, even if there is a change in hardness due to the material of the mark core 14, the size of the mark and the density of the mark can be adjusted by adjusting the pressing force, and at the same time, the durability of the mark core 14 can be improved.

  Moreover, since the socket part 10 is comprised so that isolation | separation into the socket main-body part 11 and the socket front-end | tip part 20 and both are connected with the connection metal fitting 17 and the rubber band 18, the socket front-end | tip part 20 is connected to a socket. The marking part 13 which has been worn out can be taken out from the main body part 11 and can be easily replaced with a new marking part 13, and ink can be supplied into the marking container main body 15. Further, since the connection fitting 17 and the rubber band 18 are configured as connection means that can be prevented from being detached, the socket tip 20 does not fall off the socket body 11 during use.

  Then, by repeating this operation, a large number of bolts B are tightened, and marking is performed on the heads of the bolts B.

  Note that the present invention is not limited to the above-described embodiment. For example, the configuration of the connecting means for connecting the socket tip 20 to the socket body 11 may be another form shown in FIGS. 15 to 18.

  In the embodiment of FIG. 15, the socket body portion 11A of the socket portion 10 is formed with a small-diameter connecting portion 111A that fits into the socket tip portion 20A at the tip of the large-diameter body portion 112A. On the outer peripheral surface of the connecting portion 111A, connecting grooves 51 are formed at two positions at intervals of 180 ° with respect to the axis. Each of the connecting grooves 51 is formed in a direction orthogonal to the rectilinear portion 511 around the intermediate portion of the connecting portion 111A and a rectilinear portion 511 extending toward the body portion 112A in the axial direction from the distal end surface of the connecting portion 111A. And the folded portion 513 which is shorter than the rectilinear portion 511 and is folded back from the tip of the orthogonal portion in the direction of the rectilinear portion 511, and is formed in a symmetrical inverted J shape. On the other hand, at the socket front end portion 20A, pins 52 that engage with the connecting groove 51 of the socket main body portion 11A are inwardly directed at an interval of 180 ° with respect to the axis around the rear portion of the large diameter portion 21A. It is attached in two places.

  The large-diameter portion 21A of the socket tip portion 20A is fitted into the connecting portion 111A of the socket main body portion 11A in a state where the respective pins 52 of the socket tip portion 20A are engaged with the connecting grooves 51 of the connecting portion 111A. Then, the pin 52 on the socket front end portion 20A side is moved from the front end of the rectilinear portion 511 of the connecting groove 51 on the socket main body portion 11A side toward the base portion side, and further, the socket front end portion 20A is rotated to obtain the orthogonal portion. It moves along the front end side from the folding | returning part 513 through 512. FIG. A gap 50 is formed between the socket tip 20A and the socket body 11A in a state where the socket tip 20A is fitted to the socket body 11A, and a rubber band 53 is attached so as to fill the gap 50. . In the rubber band 53, an inward protruding portion 531 to be inserted into the gap 50 is formed over the entire inner peripheral surface, and press-fitted so as to straddle the socket tip portion 20A and the outer peripheral surface of the socket main body portion 11A. As a result, the socket tip 20A can be prevented from falling off the socket body 11A.

  Next, in another embodiment shown in FIG. 16, the socket body 11B is formed with a large-diameter body part 112B and a connecting part 111B having a smaller diameter than the body part 112B, which is disposed on the distal end side of the body part 112B. Yes. Pin holes 54 are formed at two positions at 180 ° intervals with respect to the axial center at an intermediate position in the length direction of the connecting portion 111B.

  On the other hand, the socket front end portion 20B is formed in a stepped cylindrical shape having a large diameter portion 21B and a small diameter portion 23B, and an arc groove 55 having an arcuate cross section on one side is formed on the outer peripheral surface of the intermediate portion of the large diameter portion 21B. . In the arc groove 55, pin holes 56 are formed at two positions at intervals of 180 ° with respect to the axis.

  After the socket tip 20B is moved so that the connecting portion 111B of the socket body 11B is inserted into the large diameter portion 21B of the socket tip 20B, the pin hole 54 formed in the connecting portion 111B of the socket body 11B and the socket The socket holes 11B and the socket tip 20B are connected by aligning the pin holes 56 of the tip 20B and driving the pins 57 respectively. Then, a rubber band (O-ring) 58 is fitted into the arc groove 55 to prevent the pin 57 from coming off.

  Next, in still another embodiment shown in FIG. 17, after inserting a connecting portion (not shown) of the socket main body portion 11C into the large diameter portion 21C of the socket front end portion 20C, the outer periphery of the body portion 112C of the socket main body portion 11C. The first connection fitting groove 59 formed along the axial direction of the surface and the second connection fitting groove 60 formed along the axial direction of the outer peripheral surface of the large diameter portion 21C of the socket tip 20C. And the connecting fitting 61 is engaged with the first connecting fitting groove 59 and the second connecting fitting groove 60. As a result, the socket body 11C and the socket tip 20C are connected.

  At this time, the first connecting metal groove 59 is formed along the axis of the trunk portion 112C of the socket main body 11C and has a shallow groove 591 having a shallow depth, and the end of the long groove 591 extends from the end of the socket main body 11C. A deep groove portion 592 deeper than the long groove portion 591 is formed in the axial direction of the body portion 112C.

  On the other hand, the second connecting metal groove 60 is formed along the axial center of the large-diameter portion 21C of the socket tip portion 20C and has a shallow depth, and the socket tip portion 20C extends from the end of the long groove portion 601. A deep groove portion 602 deeper than the long groove portion 601 is formed in the axial direction of the large diameter portion 21C.

  The connecting fitting 61 is formed to have a length obtained by adding both the long groove portion 591 and the long groove portion 601, and has leg portions 611 that match the depths of both the deep groove portions 592 and the deep groove portions 602 at both ends. Has been. Then, after engaging the connecting fitting 61 with the first connecting fitting groove 59 and the second connecting fitting groove 60, the ring-shaped rubber band 62 having a width longer than the length of the connecting fitting 61 is used. The connecting metal fitting 61 is prevented from coming off by fitting into the outer peripheral surfaces of the socket body 11C and the socket tip 20C so as to straddle the socket body 11C and the socket tip 20C.

  Next, in still another embodiment shown in FIGS. 18 to 19, the socket main body portion 11 </ b> D has a large-diameter body portion 112 </ b> D and a small-diameter connecting portion 111 </ b> D formed at the tip of the body portion 112 </ b> D. The connecting portion 111D is formed with a first pin insertion hole 63 penetrating in a direction perpendicular to the axis at a position eccentric to the axis. On the other hand, the socket tip portion 20D includes a large-diameter portion 21D and a small-diameter portion 23D in which the connecting portion 111D is fitted. A second pin insertion hole 64 is formed through the large diameter portion 21 at a position that coincides with the connecting portion 111D of the socket main body portion 11D.

  After the connecting portion 111D of the socket main body portion 11D is inserted into the large diameter portion 21D of the socket front end portion 20D, the first pin insertion hole 63 formed in the connecting portion 111D of the socket main body portion 11D and the socket front end portion 20C. The connecting pin 65 is driven in alignment with the second pin insertion hole 64 of the large diameter portion 21C. As a result, the socket body 11D and the socket tip 20D are connected. Then, a rubber band 66 is fitted into the outer peripheral surface of the socket front end portion 20D into which the connecting pin 65 has been driven to prevent the connecting pin 65 from coming off.

  As described above, the connection structure for connecting the socket body 11 and the socket tip 20 may be configured to have a retaining means so that the socket tip 20 does not fall off the socket body 11. The connection structure is not limited to the above.

DESCRIPTION OF SYMBOLS 1 Impact wrench 10 Socket part 11 Socket main part 111 Spline shaft part 13 Marking part 14 Mark core 15 Marking container main body 17 Connecting metal fitting 18 Rubber band 20 Socket front-end | tip part 30 2nd air circuit 31 Air source 32A Regulator 33 Electromagnetic valve 34 Timer 35 Control device 36 Flow control valve

Claims (4)

A screw tightening tool main body, and a marking means that is rotatably attached to the output shaft of the screw tightening tool main body and has a screw head that is fastened at one end and can be applied to the screw head at the other end. And a marking portion for confirming that the screw is fastened with a predetermined torque by attaching ink to the head of the screw fastened by the marking means. A screw tightening tool,
The marking means includes a mark core for attaching the ink to the head of the screw and a marking container body for replenishing the mark core with ink, and an axial direction in the socket portion by air supply means for supplying compressed air slidably configured along,
The socket part is configured to be separable into a socket body part that holds the marking container body and a socket tip part that is connected to the socket body part, and the socket body part and the socket tip part are detached. It is connected by connecting means formed to be able to stop,
The socket body part has a spline shaft in which spline protrusions and spline grooves are alternately formed at the tip of the socket body part, and the spline shaft is located at a portion of the socket tip part facing the socket body part. A spline hole that fits into the socket body, and the socket body and the socket tip are connected by a spline mechanism,
The air supply means has an air circuit arranged separately from the drive means for rotating the socket portion, and an electromagnetic valve that opens after the screw tightening torque reaches a predetermined torque and rotation of the socket portion is stopped; With
A screw tightening tool with a marking function, wherein the electromagnetic valve is controlled so as to be kept open for a predetermined time. The coupling means includes a coupling fitting formed in a ring shape and disposed between the socket main body and the socket tip, and an inner protrusion that can be engaged with a spline groove formed in the socket main body. And an outer protrusion that can be engaged with a groove formed on the inner peripheral surface of the base portion on the socket tip portion side, and formed so that the socket body portion and the socket tip portion can be connected to each other. The screw tightening tool with a marking function according to claim 1 . The connecting means includes a rubber band that externally fits the connecting metal, and the rubber band includes a first notch formed in the connecting metal and a second notch formed in the socket main body. 3. The screw tightening tool with a marking function according to claim 2, wherein the screw tightening tool has a marking function, and has a positioning projection to be engaged, and is disposed so as to be externally fitted to the connection fitting. The marking function according to any one of claims 1 to 3, wherein a ring-shaped magnet for preventing the bolt from falling off is disposed on an inner peripheral surface of the socket front end facing the screw head. Screw tightening tool.

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