JP7422975B2 - Projection nut feeding rod device - Google Patents

Description

The present invention relates to a projection nut supply rod device that skewers a supply rod through a projection nut that is stopped at a predetermined position and supplies the projection nut to an electrode for electric resistance welding.

Japanese Unexamined Patent Publication No. 2002-172470 describes that a supply rod is skewered through a projection nut that is stopped at a predetermined position, and the projection nut is supplied to an electrode for electric resistance welding. However, if impurities such as iron chips enter the interior through the long hole of the supply rod, malfunctions may occur in the sliding parts, but no countermeasures are described. Also. There is also no description regarding adjustment work when changing the extension length of the supply rod.

Japanese Patent Application Publication No. 2002-172470

With the structure described in Patent Document 1, impurities such as iron scraps and welding spatter enter the sliding portion of the supply rod through the long holes provided in the outer cylinder and the long holes provided in the supply rod. , which interferes with smooth sliding movement. Furthermore, the structure makes it extremely difficult to change the position of the sensor when changing the extension length of the supply rod.

The present invention was provided in order to solve the above-mentioned problems, and it maintains the inside of the projection nut supply rod device in a good condition free from intrusion of impurities, and changes the operating state of the supply rod. It is intended to be done easily.

The invention according to claim 1 is
In a type of projection nut that is stopped at a predetermined position, a supply rod is passed through the threaded hole in a skewer shape, and this projection nut is supplied to an electrode for electric resistance welding.
The supply rod includes a large-diameter tubular rod with a sliding hole formed therein, and a small-diameter guide rod inserted into the sliding hole in a movable state,
The supply rod is housed in an outer cylinder in a state where it can move forward and backward,
A first elongated hole is formed in the large diameter rod along the central axis direction of the device, and a detected portion fixed to the small diameter guide rod enters into the first elongated hole,
A spring chamber is formed between an end of the small diameter guide rod in the sliding hole and an inner end surface of the sliding hole,
A compression coil spring that applies tension in the extrusion direction to the small diameter guide rod is disposed in the spring chamber,
The detected portion is pressed against the end of the first elongated hole by the tension of the compression coil spring, and a maximum protrusion length of the small diameter guide rod with respect to the large diameter rod is set.
A second elongated hole having width and length substantially the same as the width and length of the first elongated hole is provided in the outer cylinder along the central axis direction of the device,
The first elongated hole and the second elongated hole are in a positional relationship in which they communicate over almost the entire area,
A plate-shaped lid member that closes the second elongated hole is fixed to the outer cylinder,
A sensor is attached to the lid member in a state where the attachment position can be changed,
The mounting position of the sensor with respect to the lid member is set so that it can be detected that the detected part has stopped at a predetermined position due to advancement of the supply rod,
The projection characterized in that a structure that allows the mounting position to be changed is adopted at the mounting location of the sensor in order to correspond to a change in the stopping position of the detected portion due to a change in the extension length of the supply rod. Nut feeding rod device.

Depending on the arrangement of the electric resistance welding device and the arrangement space of the supply rod device, the extending length of the supply rod may be lengthened or shortened. In such a case, since the stopping position of the detected part pressed against the end of the first elongated hole is also changed, the position of the sensor attached to the lid member must also be changed. In the present invention, since the sensor is attached to the lid member, when changing its attachment position, it can be done with a simple replacement work, and the sensor position adjustment mechanism and adjustment work can be simplified. can.

By attaching the lid member, impurities such as iron chips and welding spatter can be prevented from entering the inside, and the sliding portion can operate smoothly. Since the sensor is attached to the lid member, the mounting position of the sensor can be adjusted and impurities can be blocked at the same time, making it possible to simplify the structure and increase functionality at the same time.

When the lid member is made of a plate-like member, the sensor is moved along the longitudinal direction of both the first and second elongated holes to change the mounting location of the sensor, making it easier to change the sensor position. Become.

The first long hole and the second long hole are in a positional relationship that communicates over almost the entire area, so if the detected part corresponds correctly to the sensor, the presence of the detected part will be reliably detected, increasing the detection reliability of the device. performance and operational reliability are improved. Further, by extending the tip portion of the detected portion until it enters the second elongated hole, the detected portion and the sensor can be placed in a close positional relationship, and the detection accuracy of the sensor is improved.

The length of the first elongated hole and the second elongated hole can be lengthened or shortened in advance in anticipation of a change in the position of the detected part due to a change in the extension length of the supply rod. This makes it easier to accommodate changes in various advancement lengths.

Although the present invention is a projection nut supply rod device, it can also exist as a method for adjusting the operation of a supply rod focusing on changing the mounting position of a sensor.

They are a side view of the entire device and a sectional view of each part. FIG. 3 is a cross-sectional view showing a displaced state of the guide rod. FIG. 2 is a side view seen from the arrow (3) direction in FIG. 1(C). It is a sectional view showing a stopper structure of a supply rod. FIG. 2 is a plan view and a sectional view showing a sensor mounting structure.

EMBODIMENT OF THE INVENTION Hereinafter, the form for implementing the projection nut supply rod apparatus of this invention is demonstrated.

1 to 5 illustrate embodiments of the invention.

First, the projection nut will be explained.

Note that in the following description, the projection nut may be simply expressed as a nut.

As shown in FIG. 2A, the iron projection nut 1 has a screw hole 3 drilled in the center of a square nut body 2, and welding protrusions 4 provided at the four corners of one side. be. The dimensions of each part of the nut 1 in this example are as follows: one side of the nut body 2 is 13 mm, the inner diameter of the screw hole 3 is 6 mm, and the thickness of the nut body 2 is 6 mm.

Next, the supply rod will be explained.

FIG. 1(B) shows the supply rod 5 alone. The symbol OO indicates the central axis of the supply rod 5, and the entire apparatus is tilted so that it is tilted. The supply rod 5 is mainly composed of a large diameter rod 6 and a small diameter guide rod 7 having a circular cross section. The large-diameter rod 6 is composed of a tubular member having a sliding hole 8 with a circular cross section formed in the center, and has a square cross-sectional shape as shown in FIG. 1(E). By having such a square cross-sectional shape, the large diameter rod 6 is prevented from rotating.

The small-diameter guide rod 7 is composed of a solid rod-like member with a circular cross section, and is inserted into the sliding hole 8 in a manner that it can move forward and backward. The insertion here should be such that there is no gap between the inner surface of the sliding hole 8 and the outer circumferential surface of the small diameter guide rod 7, and there is no sense of wobbling due to the gap when the small diameter guide rod 7 is moved in the diametrical direction. has been done. In FIG. 1B, the entire region into which the small diameter guide rod 7 is inserted is slidable without any gaps, but a plurality of such slidable regions may be partially arranged. That is, this is a case where the inner diameter of the sliding hole 8 is partially enlarged.

The operating state in FIGS. 1(B) and 1(C) is a normal state in which the supply rod 5 is advanced and the tip of the small diameter guide rod 7 is stopped just before the electrode guide pin 10 of the fixed electrode 9. . The relative position of the small diameter guide rod 7 with respect to the large diameter rod 6 is such that the small diameter guide rod 7 protrudes the most with respect to the large diameter rod 6. A steel plate component 11 is placed on the fixed electrode 9, and the electrode guide pin 10 penetrates through a pilot hole 12 of the steel plate component 11 and projects.

The fixed electrode 9 described above is an electrode for electric resistance welding, and the movable electrode 15 of the other party is illustrated in FIG. 1(A) and FIG. 2(A). The nut 1 is then welded to the steel plate component 11 by advancing the movable electrode and applying welding current.

Next, the spring chamber will be explained.

A spring chamber 16 is formed between the end surface 13 of the small-diameter guide rod 7 in the sliding hole 8 and the inner end surface 14 of the sliding hole 8 . A compression coil spring 17 is disposed within the spring chamber 16, and its tension acts in a direction to push out the small diameter guide rod 7.

Next, the temporary locking chamber will be explained.

The supply rod 5 is housed in an outer cylinder 18 so as to be able to move forward and backward, and a square hole 19 is provided in a part of the inside of the outer cylinder 18, through which the large diameter rod 6 slides. A nut supply pipe 20 extending from a parts feeder (not shown) has a rectangular cross section in order to allow the square nut 1 to pass therethrough. A nut supply pipe 20 is welded to the end of the outer cylinder 18. In the figure, welding locations are shown filled in black. As is clear from FIG. 1(D), a temporary locking chamber 21 is formed at the intersection of the outer cylinder 18 and the nut supply pipe 20. Reference numeral 22 indicates an outlet opening of the supply rod 5 or the nut 1.

The wall thickness of the outer cylinder 18 is set to be large in order to increase the strength and rigidity of the outer cylinder 18 itself and improve the installation stability of the device. This outer cylinder 18 is fixed to a stationary member 29 such as a machine frame to which this device is attached.

When the nut 1 advances in the longitudinal direction of the nut supply pipe 20 and enters the temporary locking chamber 21, it is received by the stop guide plate 23 and the nut 1 is positioned. That is, as shown in FIG. 1(D), the screw hole 3 of the nut 1 and the small diameter guide rod 7 are coaxial. A flat portion 24 is formed near the lower end of the outer cylinder 18, and a stop guide plate 23 is pressed onto the flat portion 24. The stop guide plate 23 is pressed against the flat part 24 and fixed by a fixing bolt 26 screwed into a support piece 25 fixed to the outer cylinder 18. A permanent magnet 27 is embedded in the stop guide plate 23, and the nut 1 is drawn into the temporary locking chamber 21 by this attractive magnetic force.

The distal end of the nut supply pipe 20 is bifurcated, and the stop guide plate 23 is abutted against the distal end of the bifurcated portion to form a space for the temporary fixing chamber 21. A through hole 28 is formed in the ceiling side portion of the nut supply pipe 20, through which the large diameter rod 6 passes.

Next, the means for advancing and retracting the supply rod will be explained.

Various means can be used to move the supply rod 5 forward and backward, such as an air cylinder, an electric motor with forward and backward output, and a rack and pinion mechanism. An air cylinder is used here.

An air cylinder 30 is connected to the outer cylinder 18, and a piston rod 31 of the air cylinder 30 is connected to the large diameter rod 6. The dimensions of each part are selected so that when the air cylinder 30 is moved back the most, the tip of the small-diameter guide rod 7 is at a position slightly retreated from the temporary locking chamber 21, as shown in FIG. 1(D).

Next, a structure for regulating the advancement length of the small diameter guide rod will be explained.

A first elongated hole 32 is formed in the large diameter rod 6 in the direction of the central axis OO. A detection projection 33 fixed to the small-diameter guide rod 7 with a bolt or the like enters the first elongated hole 32 . Here, it protrudes from the first long hole 32 to the outside. The protrusion 33 is formed with a fixed part 34 and a detected part 35 in an L-shape, the fixed part 34 is fixed to the small diameter guide rod 7 with bolts, and the detected part 35 is formed in the first elongated hole as described above. It is entering the 32nd year. Here, the detected portion 35 protrudes from the first elongated hole 32 .

A second elongated hole 37 is formed in the outer cylinder 18 in the direction of the central axis OO. As shown in FIG. 3, the second elongated hole 37 is set to have substantially the same shape and dimensions as the first elongated hole 32 formed in the large diameter rod 6. As seen in FIG. 1C, the detected portion 35 is disposed within the second elongated hole 37 without protruding outward from the second elongated hole 37, and is aligned within the second elongated hole 37 with the central axis O- It is now possible to move forward and backward in the O direction.

Since the tension of the compression coil spring 17 is acting on the small-diameter guide rod 7, the protrusion 33 fixed to the small-diameter guide rod 7 is pressed against the lower end surface 38 (see FIG. 3) of the long hole 32, and the large-diameter rod The maximum protrusion length of the small-diameter guide rod 7 is set. The distance in the central axis OO direction of the spring chamber 16 at this time is the maximum distance. Note that the lower end surface 36 of the large diameter rod 6 is used as the extrusion surface of the nut 1 waiting in the temporary locking chamber 21.

Next, the sensor will be explained.

The sensor indicated by the reference numeral 40 emits a detection signal when the detected part 35 stops at the normal position, as shown in FIG. 1(C). If the second elongated hole 37 and the first elongated hole 32 are exposed in an open state, there is a possibility that iron scraps or some kind of dust particles may enter the respective elongated holes and interfere with the sliding operation. In order to solve this problem, a plate-shaped cover member 41 that closes off the second elongated hole 37 is attached by bolting or the like. Note that various types of sensor 40 can be employed, and for example, a capacitive proximity sensor is suitable. In addition, in FIG. 3, the lid member 41, the second elongated hole 37, the outer cylinder 18, etc. are shown by two-dot chain lines for easy understanding.

In order to accurately detect the detected part 35 stopped at a normal position, the relative positions of the sensor 40 and the detected part 35 are set correctly. In order to do this, the sensor 40 is placed in the correct position when the lid member 41 is attached to a predetermined position. Here, as shown in an enlarged view in FIG. 1(E), a recess 42 is formed in the lid member 41, and the sensor 40 is fitted and attached thereto. Reference numeral 43 is a signal line of the sensor 40.

As shown in FIG. 1C, when the relative positions of the sensor 40 and the detected portion 35 are set correctly, the movable electrode 15 advances at a predetermined time based on a signal from the sensor 40. Such operations can be performed by a common control system.

To explain the above control system based on this embodiment, for example, when an operator inputs a start signal to a control device composed of a simple computer device or a sequence circuit, a command signal from the control device activates the air switching valve. operates, and the supply rod 5 advances by a predetermined stroke of the air cylinder 30. As a result of this advance, the nut 1 through which the small-diameter guide rod 7 has passed slides down the small-diameter guide rod 7 and is correctly supplied to the electrode guide pin 10, and then the supply rod 5 stops advancing (at this advance stop position). (setting will be described later), the relative positions of the sensor 40 and the detected part 35 are set correctly so that they face each other. At this time, a signal sent from the sensor 40 causes the control device to send an advance permission signal for the movable electrode 15, and welding of the nut to the steel plate component 11 is completed. Device operation centered on the above-mentioned control device is also described in the above-mentioned Patent Document 1.

Next, the distance in the center axis direction of the spring chamber will be explained.

As shown in FIGS. 1(B) and 2(C) and FIG. 2(B), when the supply rod 5 is advancing normally, the distance in the center axis direction of the spring chamber 16 is the maximum length L1. . As shown in FIG. 2(A) due to the worker's carelessness, the worker's hand may get caught between the small diameter guide rod 7 and the electrode guide pin 10, and usually the worker's fingers are often caught. . In such a situation, the stopped small diameter guide rod 7 is pushed relatively in the backward direction of the central axis OO direction by the advancement of the large diameter rod 6. At this time, the small diameter guide rod 7 advances into the spring chamber 16 while compressing the compression coil spring 17. This pushing length is the distance between the tip of the small-diameter guide rod 7 and the electrode guide pin 10 when the finger is pinched, that is, the pinching danger distance L2, which corresponds to the thickness of the finger.

The distance between the small-diameter guide rod 7 and the electrode guide pin 10, that is, the pinching danger distance L2, which corresponds to the thickness of a finger, is approximately 16 to 19 mm for male workers and 13 to 19 mm for female workers, as described above. It is appropriate to recognize it as approximately 16 mm. That is, the pinching danger distance L2 is determined based on the dimensions listed here. Here, L2 is 19 mm, which is the thick finger of the elastic worker.

The distance L1 in the central axis OO direction of the spring chamber 16 is set to be at least three times the pinching hazard distance L2 when the operator's hand is pinched between the small diameter guide rod 7 and the electrode guide pin 10. ing. The pinching danger distance L2 here is 66.5 mm, which is equivalent to 3.5 times.

By setting the distance L2 to be three times or more, the spring reaction force does not become large when the distance L2 is short, that is, when the compression length of the compression coil spring 17 is short and the spring reaction force is small. This is preferable in terms of worker protection, as it causes only mild pain or mild symptoms.

If the distance L1 is less than three times the distance L2, the distance L1 will be too short, and the elastic reaction force of the compression coil spring 17 acting on the finger will become large, resulting in insufficient worker protection. If the distance L1 is 5 times or more the distance L2, it is good in terms of reducing the spring reaction force against the fingers, but there is a risk that the pushing force of the small diameter guide rod 7 by the compression coil spring 17 will be insufficient, and the supply This is unfavorable in terms of making the rod 5 and the entire device more compact.

FIG. 1(E) is a sectional view taken along the line EE in FIG. 1(C), but is also a sectional view taken along the line EE in FIG. 1(A).

Next, a structure for adjusting the extension length of the supply rod will be explained.

In the above-described operation, it is necessary to correctly stop the tip of the small-diameter guide rod 7 just in front of the electrode guide pin 10, as shown in FIG. 1(C).

In other words, the extension length of the supply rod 5 is set to a predetermined length. Various structures can be adopted for this purpose, and one example is the structure shown in FIG. 4(A). Here, the structure is such that a circular flange 44 fixed to the end of the large diameter rod 6 is stopped by abutting against a stopper surface 45 formed inside the outer cylinder 18. The flange 44 is fixed between the large diameter rod 6 and the piston rod 31. Therefore, when the supply rod 5 is advanced by the air cylinder 30, the flange 44 is received by the stopper surface 45, and the tip of the small diameter guide rod 7 is stopped at the correct position. In other words, the advancing position of the supply rod 5 is determined.

When the location of the fixed electrode 9, that is, the location of the electric resistance welding device, is changed, it is necessary to change the maximum extension length of the supply rod 5 to accommodate this change. Various structures can be adopted to deal with this. Here, as a simple example, this is handled by changing the position of the stopper surface 45. In the case shown in FIG. 4(B), a cylindrical adjustment member 47 is press-fitted into the outer cylinder 18 to change the position of the stopper surface 45, and the new annular stopper surface is indicated by reference numeral 45a. ing. In this case, the maximum advancing distance of the supply rod 5 is shortened by the length L3 of the adjusting member 47. Conversely, if the stopper surface 45 is moved toward the distal end side of the supply rod 5 by cutting, the maximum advancing distance of the supply rod 5 will become longer.

Furthermore, instead of the above method, it is also possible to adopt control that changes the stroke of the air cylinder 30. That is, although not shown, a piston position detection switch is attached to the outer peripheral surface of the air cylinder 30, and the advancing operation of the air cylinder 30 is stopped by a signal transmitted when the piston movement amount reaches a predetermined amount.

Next, changing the position of the sensor will be explained.

The position of the sensor 40 is changed by changing the attachment position of the sensor 40 to the lid member 41. Various methods can be adopted for this change. If there is a change in the advancing length of the supply rod 5 as described in accordance with FIG. 4, the stopping position of the detected portion 35 will change, and therefore the sensor position will need to be changed.

FIG. 5(A) shows the cover member 41 removed from the outer cylinder 18 turned over. As also shown in FIG. 5(B), the sensor 40 is fitted into the groove-shaped depression 42 and the bolt is inserted. 48, which is fixed to the lid member 41.

A plurality of depressions 42 are provided, and are provided in advance in anticipation of the location where the detected portion 35 will change its stop position. Here, four depressions 42 are provided. For example, it is also possible to provide a plurality of depressions 42 at regular intervals, or to provide irregular intervals.

In the example shown in FIG. 5(C), the plurality of depressions 42 as described above are stopped, the back surface 49 of the lid member 41 is made a flat surface, and the screw hole position of the bolt 48 is provided freely, making it easy to change the position. Compatible. As shown by the two-dot chain line, it can be moved freely by sliding it to the required location.

Next, the operation of the device will be explained.

In the state before the start of operation of the device, the protrusion 33 is pressed against the lower end surface 38 of the first elongated hole 32 by the elasticity of the compression coil spring 17, and the air cylinder 30 is retracted as far as possible, as shown in FIG. 1(D). As shown in FIG. 2, the tip of the small-diameter guide rod 7 is placed in a position retracted from the temporary locking chamber 21.

Here, when the supply rod 5 advances due to the advancing operation of the air cylinder 30, the small-diameter guide rod 7 enters the threaded hole 3 of the nut 1 waiting in the temporary locking chamber 21 to form a skewer shape, and further advances to the extrusion surface. 36 pushes the upper surface of the nut 1, the nut 1 is sent out while rubbing against the stop guide plate 23, and the nut 1 slides down the small diameter guide rod 7. When the advance of the supply rod 5 stops just before the electrode guide pin 10, the nut 1 is transferred onto the steel plate component 11 by inertia. At this time, the electrode guide pin 10 relatively enters the screw hole 3, and the positioning of the nut 1 is completed.

When nut supply is completed as described above, since the protrusion 33 is pressed against the lower end surface 38 of the first elongated hole 32, the detected part 35 correctly faces the sensor 40, so the sensor emitted at this time The movable electrode 15 is advanced in response to the signal 40. Before the movable electrode 15 advances, the supply rod 5 is retracted in advance so that the movable electrode 15 can advance and pressurize the nut 1. Thereafter, welding current is applied to complete electric resistance welding.

As shown in FIG. 2A, when the operator's finger is caught between the small-diameter guide rod 7 and the electrode guide pin 10, the small-diameter guide rod 7 moves into the spring chamber 16 while relatively compressing the compression coil spring 17. be pushed back to Due to such push-back displacement, the detected portion 35 stops at a position shifted from the sensor 40, so that the sensor 40 does not transmit an electrode advance permission signal. Therefore, the movable electrode 15 is not advanced, and there is no danger of fingers being caught between the electrodes.

Although the above-mentioned embodiment focuses on worker safety, the phenomenon in which the small-diameter guide rod 7 is pushed into the large-diameter rod 6 can be caused by, for example, a tool such as a spanner, a steel plate part with a square cross section, etc. However, this also occurs when the electrode guide pin 10 is caught between the small diameter guide rod 7 and the electrode guide pin 10 for some reason.

The effects of the embodiment described above are as follows.

Depending on the arrangement of the electric resistance welding device and the arrangement space of the supply rod device, the extending length of the supply rod 5 may be lengthened or shortened. In such a case, the stopping position of the detected part 35 pressed against the end 38 of the first elongated hole 32 is also changed, so the position of the sensor 40 attached to the lid member 41 must also be changed. Must be. In the present invention, since the sensor 40 is attached to the lid member 41, when changing its attachment position, it can be done with a simple replacement work, which simplifies the position adjustment mechanism of the sensor 40 and the adjustment work. can be achieved.

By attaching the lid member 41, impurities such as iron chips and welding spatter can be prevented from entering the inside, and the sliding portion can operate smoothly. Since the sensor 40 is attached to the lid member 41, the attachment position of the sensor 40 can be adjusted and impurities can be blocked at the same time, and the structure can be simplified and multifunctionalized at the same time.

When the lid member 41 is made of a plate-like member, the sensor 40 is moved along the longitudinal direction of both the first and second elongated holes 32 and 37 to change the mounting location of the sensor 40. This makes it easier to change the position of the sensor 40.

Since the first elongated hole 32 and the second elongated hole 37 are in a positional relationship in which they communicate over almost the entire area, when the detected part 35 correctly corresponds to the sensor 40, the presence of the detected part 35 is reliably detected. The detection reliability and operational reliability of the device are improved. Moreover, by extending the tip of the detected part 35 until it enters the second elongated hole 37, the detected part 35 and the sensor 40 can be placed in a close positional relationship, and the detection accuracy of the sensor 40 is improved.

The lengths of the first elongated hole 32 and the second elongated hole 37 can be made longer or shorter in advance in anticipation of a change in the position of the detected part 35 due to a change in the length of the supply rod 5's advancement. Therefore, it becomes easier to accommodate various changes in the extension length of the supply rod 5.

As described above, according to the device of the present invention, it is possible to maintain the interior of the projection nut supply rod device in a good condition free from intrusion of impurities, and to easily change the operating state of the supply rod. can. Therefore, it can be used in a wide range of industrial fields, such as automobile body welding processes and sheet metal welding processes for home appliances.

1 Projection nut 5 Supply rod 6 Large diameter rod 7 Small diameter guide rod 8 Sliding hole 9 Fixed electrode 10 Electrode guide pin 11 Steel plate component 13 End surface 14 Inner end surface 15 Movable electrode 16 Spring chamber 17 Compression coil spring 18 Outer cylinder 19 Square hole 21 Temporary locking chamber 30 Air cylinder 32 First elongated hole 33 Protrusion 34 Fixed part 35 Detected part 36 Lower end surface (extruded surface)
37 Second elongated hole 38 Lower end surface 40 Sensor 41 Lid member 42 Recess 49 Back surface O-O Center axis L1 Center axis distance of spring chamber L2 Danger of pinching distance

Claims (1)

In a type of projection nut that is stopped at a predetermined position, a supply rod is passed through the threaded hole in a skewer shape, and this projection nut is supplied to an electrode for electric resistance welding.
The supply rod includes a large-diameter tubular rod with a sliding hole formed therein, and a small-diameter guide rod inserted into the sliding hole in a movable state,
The supply rod is housed in an outer cylinder in a state where it can move forward and backward,
A first elongated hole is formed in the large diameter rod along the central axis direction of the device, and a detected portion fixed to the small diameter guide rod enters into the first elongated hole,
A spring chamber is formed between an end of the small diameter guide rod in the sliding hole and an inner end surface of the sliding hole,
A compression coil spring that applies tension in the extrusion direction to the small diameter guide rod is arranged in the spring chamber,
The detected portion is pressed against the end of the first elongated hole by the tension of the compression coil spring, and a maximum protrusion length of the small diameter guide rod with respect to the large diameter rod is set.
A second elongated hole having width and length substantially the same as the width and length of the first elongated hole is provided in the outer cylinder along the central axis direction of the device,
The first elongated hole and the second elongated hole are in a positional relationship in which they communicate over almost the entire area,
A plate-shaped lid member that closes the second elongated hole is fixed to the outer cylinder,
A sensor is attached to the lid member in a state where the attachment position can be changed,
The mounting position of the sensor with respect to the lid member is set so that it can be detected that the detected part has stopped at a predetermined position due to advancement of the supply rod,
The projection characterized in that a structure that allows the mounting position to be changed is adopted at the mounting location of the sensor in order to correspond to a change in the stopping position of the detected portion due to a change in the extension length of the supply rod. Nut feeding rod device.

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