JP2023106802A - Automatic screw fastening machine - Google Patents

Abstract

To provide an automatic screw fastening machine which can shorten an operation time per one cycle.SOLUTION: An automatic screw fastening machine 1 comprises: a feeding member 10 which can pass a separately supplied screw N; a chuck 20 which receives the screw N discharged from one end of the feeding member 10 and can suspend and support the same; a screw guide 30 which adsorbs the screw N from the chuck 20, and can hold the same; and a bit B which is so arranged as to be capable of being inserted through the screw guide 30 and is rotatable, and engages with the screw N. The chuck 20 is connected to transfer means 40 which can reciprocate from one end side of the delivery member 10 to a tip side of the screw guide 30. A suspension hole 20a communicates with a cleaning unit, which sucks air and recovers deposits on the suspended screw N, and an air intake port 20d crossing the suspension hole 20a.SELECTED DRAWING: Figure 2

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic screwdriver that sucks and removes deposits adhering to a separately supplied screw, and then screws the cleaned screw into a workpiece for fastening.

As shown in Patent Document 1, a conventional automatic screw tightening machine includes a motor connected to a bit that can be engaged with a screw, which is an example of a fastening part, to rotationally drive the bit, and a motor arranged on the tip side of the bit. A chuck capable of suspending and supporting the separately supplied screw, a screw feeder connected to the chuck by a hose and capable of pneumatically feeding the screw into the chuck, and feeding the screw supplied to the chuck to the tip of the bit. It comprises a sucking mechanism capable of sucking and holding, and a suction duct which is arranged so as to surround the chuck and is capable of sucking all the surplus air discharged out of the chuck by air pressure feeding.

The suction mechanism comprises a screw guide having an inner diameter that allows the bit and screw to pass through, and an air suction means connected to the inside of the screw guide and operated to create a negative pressure in the bit insertion path. . The screw guide is always in contact with the spring and contains the bit. As a result, the tip of the screw guide is pushed toward the motor, causing the spring to bend. Thus, the bit can be relatively displaced to protrude from the previously enclosed screw guide. Also, the bit and screw guide are configured to descend together toward the work placed below the chuck. Although the suction duct is normally positioned below the chuck, it is configured to be horizontally rotatable by 90 degrees from this position.

The conventional automatic screwdriver configured in this manner turns the suction duct horizontally by 90 degrees and then lowers the bit to tighten the screw, so the suction duct is removed from the descending path of the bit. be able to.

Japanese Patent Publication No. 07-110454

However, in the conventional automatic screwdriver, the suction duct must be horizontally turned before the bit is lowered, so there is a problem that the work time per cycle is lengthened by the time required for this turn. Further, in the conventional automatic screw tightening machine, the chuck is fixedly arranged on the path of the bit that descends, so the bit is inserted into the chuck while the screw is being fastened to the workpiece. It's becoming Therefore, since the next screw cannot be supplied to the chuck while the screw is being tightened, there is also the problem that the working time per cycle cannot be greatly reduced.

The present invention provides a feeding member through which a separately supplied screw can pass, a chuck having a suspension hole capable of receiving and supporting the screw ejected from one end of the feeding member, and the chuck. a screw guide capable of picking up the screw by suction from the screw guide; and a bit inserted through the screw guide and rotatably engaged with the screw. In an automatic screwdriver equipped with a transfer means capable of reciprocating toward the tip of a screw guide, the suspension hole includes a cleaning unit for sucking air to collect deposits on the suspended screw and a suspension hole. It is characterized in that the intake holes that intersect with are in communication with each other. The suspension hole is integrally provided with a head accommodation hole for accommodating the head of a screw and a shaft accommodation hole for accommodating the shaft of the screw, which is continuous with the head accommodation hole. It is preferable that the hole and the cleaning unit communicate with the shaft portion accommodation hole. Further, it is preferable that an intake filter is attached to an open end of the intake hole. Furthermore, it is preferable that a neutralization blower is attached to the opening end of the air intake hole. Moreover, it is preferable that a communicating hole through which a screw can pass and an exhaust hole intersecting the communicating hole are formed in the sending member. Furthermore, it is preferable that an exhaust filter is attached to the open end of the exhaust hole.

In the automatic screw tightening machine according to the present invention, since the chuck for receiving a screw is configured to be reciprocally movable from one end of the feeding member to the tip of the screw guide, the next screw is supplied during screw tightening. There are advantages such as being able to shorten the cycle time. In addition, the chuck is formed with a hanging hole for supporting the screw in a suspended manner, and the cleaning unit and the air intake hole communicate with the hanging hole. Therefore, when the cleaning unit is driven, external air can flow vigorously into the suspension hole. For this reason, there is also an advantage that the cleaning unit can efficiently collect deposits on the screws. In addition, since the chuck has a suspension hole consisting of a head housing hole and a shaft housing hole connected to the head housing hole, it is easier to machine than a pair of claws rotating symmetrically. There is also the advantage of being able to reduce the manufacturing cost. In addition, since a filter is attached to the air intake hole and cleaned air flows into the suspension hole, there is an advantage that there is no risk of dust or the like adhering to the screw. Furthermore, when a static elimination blower is attached to the air intake hole, static electricity can be eliminated from the screw, and problems caused by static electricity during fastening of the substrate or the like can be prevented. Further, since the communicating member is formed with an exhaust hole, it is possible to reduce the load applied to the transfer means, which has the advantage of extending the life of the transfer means. Furthermore, since an exhaust filter is attached to the open end of the exhaust hole and the cleaned air can be discharged, there is an advantage that the surroundings of the apparatus can be kept clean.

It is a partially notched side view which shows the automatic screw fastening machine which concerns on this invention. It is a sectional view for explaining operation of an automatic screw fastener concerning the present invention. (a) is a partially cutaway cross-sectional view showing the positional relationship before operation, and (b) is an operation progressing from the state of FIG. FIG. 3 is a partially cutaway cross-sectional view of a main part showing a point in time; It is a sectional view for explaining operation of an automatic screw fastener concerning the present invention. 3(a) is a partially cutaway cross-sectional view of the main part showing the state when the operation progresses from the state of FIG. 2(b) and the chuck is transferred to the feeding member side, and FIG. FIG. 10 is a partially cutaway cross-sectional view of the essential parts showing a state in which the operation progresses from the state of (1), the bit is rotated down to perform the screw tightening work, and the next screw is supplied to the chuck.

As shown in FIGS. 1 to 3, an automatic screw tightening machine 1 according to the present invention includes a feeding member 10 through which a screw N having a head portion and a shaft portion, which is an example of a fastening part, can pass, and A chuck 20 capable of receiving the screw N ejected from one end of the member 10 and capable of supporting the suspension, and air is sucked from the lower part of the chuck 20 to remove deposits adhering to the suspended screw N. A cleaning unit, a screw guide 30 capable of sucking up the screw N from the chuck 20 and holding it inside, and a bit B arranged so as to be freely inserted and rotatable in the screw guide 30 and engaged with the screw N. It consists

The feeding member 10 is positioned in front of the screw guide 30 and is connected to a parts feeder (not shown) that feeds the screws N. As shown in FIG. The feeding member 10 is composed of a hose joint 11 to which a resin hose (not shown) extending from the parts feeder can be connected, and a base 12 to which the hose joint 11 can be tilted and fixed. The parts feeder may have a configuration in which the screws N are simply slid down into the resin hose one by one and discharged, or the screws N are forcibly fed by compressed air.

The resin hose is molded with an internal passage whose inner diameter is set to be slightly larger than the head of the screw N, and allows the screw N to pass through with the head side in the rear and the shaft side in the front. . In other words, the screw N passing through the resin hose does not rotate such that the head portion and the shaft portion are exchanged back and forth.

The hose joint 11 extends over its entire length and is provided with a passage hole 11a through which the screw N can pass in the same manner as the resin hose described above. , and a male thread on the outer circumference of the other end. The base 12 comprises a threaded portion to be screwed onto the external thread of the hose joint 11 and a communication hole 12a communicating with the threaded portion and with the passage hole 11a of the hose joint 11 . The communication hole 12a is composed of an inclined hole formed at the same inclination angle as the mounting angle of the hose joint 11 and a vertical hole extending vertically from the inclined hole. As a result, the base 12 guides the screw N through the passage hole 11a of the hose joint 11, through the inclined hole and then the vertical hole in this order, and is configured to slide down from the shaft portion side of the screw N. As shown in FIG.

Further, the base 12 is formed with an exhaust hole 12b that intersects with the communicating hole 12a. The exhaust hole 12b extends from the communication hole 12a to the surface of the base 12, and an exhaust filter 12c is attached to the surface side opening of the base 12. As shown in FIG. The exhaust filter 12c is formed in a sponge-like shape so that only air can pass therethrough and impurities such as dust in the air can be collected.

As shown in FIGS. 2(a) and 2(b), the chuck 20 has a suspension hole 20a capable of suspending support with the head of the screw N facing upward and the shaft portion facing downward. . The suspension hole 20a includes a mortar-shaped head accommodation hole that contacts the head bearing surface of the screw N, a shaft accommodation hole that is connected to the lower end of the head accommodation hole and into which the shaft of the screw N can be inserted, An internal screw portion 20b is provided so as to communicate with the shaft accommodating hole. Moreover, the chuck 20 is attached to a transfer means 40 capable of reciprocating in the horizontal direction.

A pipe joint 21 to which an air pipe (not shown) can be connected is attached to the internal thread portion 20b, and the cleaning unit (not shown) is connected through the air pipe connected to the pipe joint 21. ing. As a result, the screw N supported by the hanging hole 20a is urged downward by air suction of the cleaning unit, and the deposits adhering to the screw N are removed through the air pipe.

A sensor light hole 20c through which light emitted from a sensor 50 arranged opposite to the side surface of the chuck 20 can pass is arranged in the shaft housing hole at right angles to the shaft housing hole. As a result, the light is blocked by the shaft portion of the screw N when the screw N is suspended in the chuck 20 as shown in FIG. 3(a) and 3(b), the light passes through the sensor light hole 20c and is received by the other sensor 50 when the screw N is not supported in the chuck 20. As shown in FIG.

Further, the chuck 20 is formed with an intake hole 20d perpendicular to the shaft housing hole, and the shaft of the screw N supported by the suspension hole 20a extends along the extension of the intake hole 20d. located at a height. Therefore, when the cleaning unit drives the air suction and the inside of the shaft housing hole becomes negative pressure, external air can enter the shaft housing hole through the intake hole 20d. As described above, the flow velocity of the air in the shaft housing hole is improved, so that the deposits can be easily removed. Further, the chuck 20 is equipped with an air intake filter 20e that seals the opening of the air intake hole 20d so as to allow ventilation. The air intake filter 20e is sponge-like, and is designed to allow air to pass through and to remove impurities such as dust in the air.

The transfer means 40 comprises a movable portion 42 capable of direct reciprocating movement and a plate 41 attached to the movable portion 42 , and the chuck 20 is fixed to the tip of the plate 41 . Therefore, the chuck 20 is configured to horizontally move to two positions below the base 12 or at the tip of a screw guide 30 which will be described later. Further, the transfer means 40 is composed of an air cylinder in which the movable portion 42 extends forward when air is supplied from the outside.

The plate 41 has a through hole 41a through which the screw guide 30 can be inserted. The through hole 41a is arranged between the chuck 20 and the movable part 42, and can pass through the screw guide 30 when the communication hole 12a and the suspension hole 20a are in communication with each other. It is molded to be in a good position.

The screw guide 30 includes a bit B having a tip shape that can be engaged with the head of the screw N so that it can rotate and move up and down. is set to A pipe joint 31 similar to the pipe joint 21 attached to the chuck 20 is arranged at the upper end of the screw guide 30, and an air pipe (not shown) is connected to the pipe joint 31. Suction means (not shown) for sucking air through is installed. As a result, air is sucked through the gap between the bit B and the screw guide 30 when the suction means is actuated. 2(a), 2(b), and 3(a), the screw guide 30 is always on standby at a height substantially equal to the lower surface of the base 12. , the screw N supported by the chuck 20 can be immediately delivered to the screw guide 30 as shown in FIG. 2(b).

The bit B is directly connected to a motor M arranged above it, and is rotatable so as to be driven by the motor M to generate a predetermined rotational speed and torque. Also, the bit B is configured to be relatively movable with respect to the screw guide 30 and configured to protrude from the screw guide 30 . As a result, when the tip of the screw guide 30 comes into contact with the surface of the work W, the rotating bit B then starts relative movement to screw the screw N into the tapped hole Wa of the work W. As shown in FIG.

Further, the automatic screw tightening machine 1 according to the present invention is provided with control means (not shown), and this control means includes the component feeder, the motor M, the transfer means 40, the sensor 50, and the like. It is wired to the units, receives various signals from each unit, and is configured to be able to control the operation of each unit based on these signals.

In the automatic screwdriver 1 according to the present invention constructed as described above, the parts feeder and the cleaning unit operate simultaneously in response to a command from the control means. As a result, the component feeder supplies the compressed air and the screw N to the resin hose, while the cleaning unit starts sucking air to move the resin hose, the passage hole 11a, and the communication hole 12a in order. The passing screw N and compressed air continue to be sucked downward from the side of the internal thread portion 20b. Eventually, when the screw N is transferred from the communication hole 12a to the suspension hole 20a as shown in FIG. blocked. Further, in delivering the screw N, as described above, the communication hole 12a is composed of an inclined hole and a vertical hole, and the screw N is delivered in a posture parallel to the suspension hole 20a. and the angle difference between the hanging hole 20a and the head accommodation hole becomes large. As a result, the tip of the shaft portion of the screw N is not locked in the head accommodation hole, and reliable delivery is possible.

Incidentally, when the screw N is delivered to the suspension hole 20a as described above, the head of the screw N closes the suspension hole 20a. As a result, the compressed air supplied from the component supply device is exhausted to the outside through the exhaust hole 12b communicating with the communication hole 12a. After the suspension hole 20a is closed in this manner, the compressed air is discharged to the outside through the exhaust hole 12b. The portion 42 is prevented from being pressed downward. As a result, the load applied to the movable portion 42 of the transfer means 40 is reduced, and the life of the transfer means 40 is extended. In addition, since the exhaust filter 12c is attached to the opening of the communication hole 12a, when the compressed air is exhausted, the dust adhered to the inside of the resin hose, the passage hole 11a, and the communication hole 12a is removed from the exhaust filter. It is possible to discharge only the cleaned air collected in 12c. As a result, it is possible to prevent contamination around the device and keep it clean. Furthermore, since the exhaust is exhausted through the exhaust filter 12c, there is an advantage such as that the exhaust noise is reduced.

Further, when the light is blocked by the shaft portion of the screw N, the sensor 50 outputs a detection signal indicating that the screw N is present in the chuck 20 to the control means. Upon receiving this detection signal, the control means issues a compressed air supply stop command to the parts feeder. The cleaning unit continues to suck air even after the parts feeder has stopped supplying compressed air. At the time of this air suction, the air intake hole 20d is formed, and external air can flow into the shaft housing hole through the air intake hole 20d. Even if the is closed, the air can pass vigorously between the inner wall of the shank housing hole and the shank surface of the screw N, and the cleaning unit can more effectively remove deposits adhering to the shank surface of the screw N. Easier to collect. Furthermore, since the air intake filter 20e is attached to the opening of the air intake hole 20d, impurities such as dust in the air flowing in from the outside are removed, and the cleaned air can flow in. This prevents impurities from adhering to the shaft surface again.

Next, when the control means receives the detection signal from the sensor 50, it issues a backward movement command to the transfer means 40 to transfer the chuck 20 to the screw guide 30 side. As a result, the transfer means 40 draws in the movable portion 42 to transfer the chuck 20 to the tip side of the screw guide 30 . The transfer means 40 generates a signal from a cylinder switch (not shown) indicating that the suspension hole 20a and the screw guide 30 are coaxially positioned, and transmits the signal to the control means.

As a result, the control means issues an air suction stop command to the cleaning unit and an air suction start command to the suction means connected to the screw guide 30 . Therefore, the screw N supported by the chuck 20 is sucked up by the air sucked toward the bit B and transferred into the screw guide 30 as shown in FIG. 2(b). At this time, the air flows vigorously between the inner surface of the screw guide 23 and the screw N, so that the deposits adhering to the surface of the screw N are collected. Therefore, not only the shank of the screw N but also the deposits attached to the head are collected. In addition, since the outside air cleaned by the air intake filter 20e can flow into the hanging hole 20a through the air intake hole 20d, the backflow of air from the cleaning unit side into the hanging hole 20a is prevented. As a result, deposits collected from the shaft surface of the screw N by the cleaning unit are prevented from flowing into the suspension hole 20a and the screw guide 23 and attaching to the screw N again.

As described above, the sensor 50 becomes capable of receiving light again when the screw N is transferred to the screw guide 30, and issues a detection signal indicating that the screw N is not present in the chuck 20 to the control means. When a preset time such as 0.5 seconds elapses after receiving a detection signal from the sensor 50 indicating that the screw N is not present, the control means issues an operation command to the transfer means 40. A rotational drive command is issued to the motor M. As a result, the chuck 20 is transferred forward as shown in FIG. 3A, and moves from the distal end side of the screw guide 30 to a position where the suspension hole 20a and the communication hole 12a communicate with each other. Completion of the movement to the position of the chuck 20 is determined by the control means by receiving a signal from a cylinder switch (not shown) separately arranged in the transfer means 40 .

Next, when the control means makes the above determination, it commands the screw guide 30 and the rotating bit B to descend as shown in FIG. and contact the surface of the work W. After this abutment, the bit B begins to move relative to the screw guide 30, and the screw N, which engages with and rotates together, is screwed into the tapped hole Wa.

Further, the control means sends an operation command to the parts feeder at the same time as issuing the aforementioned command to lower the screw guide 30, and controls to feed the next screw N under pressure. Therefore, while the screw N transferred into the screw guide 30 is being fastened to the work W, the next screw N can be supplied to the chuck 20 . In other words, since the operation of screwing the screw N into the workpiece W and the operation of feeding the screw to the chuck 20 can be processed simultaneously, even if the screw tightening operation requires a long distance from the component feeder to the chuck 20, the operation required for one cycle. Save time.

The automatic screw tightening machine 1 according to the present invention is not limited to the one described above, and various modifications can be made without departing from the gist of the invention. For example, air supply means (not shown) configured to supply compressed air toward the shaft housing hole when the screw N reaches the suspension hole 20a instead of the intake filter 20e at the opening of the intake hole 20d. may be attached. In particular, when a static elimination blower (not shown) or the like is mounted instead of the intake filter 20e, even if the screws N are charged, it is possible to eliminate the static electricity. It is possible to safely tighten even a difficult work. Also, an air suction means configured to suck air while the screw N is being supplied may be provided in the opening of the exhaust hole 12b.

DESCRIPTION OF SYMBOLS 1... Automatic screw tightening machine 10... Transmission member 20... Chuck 30... Screw guide 40... Transfer means 50... Sensor B... Bit N... Screw

The present invention provides a feeding member through which a separately supplied screw can pass, a chuck having a suspension hole capable of receiving and supporting the screw ejected from one end of the feeding member, and the chuck. a screw guide capable of picking up the screw by suction from the screw guide, a bit disposed rotatably through the screw guide and engaged with the screw, and the chuck being moved from one end of the feeding member to the screw guide. In an automatic screwdriver equipped with a transfer means for reciprocating to the tip side of the screw, the suspension hole intersects with a cleaning unit for sucking air and collecting deposits on the suspended screw and the suspension hole. The air intake hole communicates with the air intake hole, and an air intake filter is attached to the air intake hole . The suspension hole is integrally provided with a head accommodation hole for accommodating the head of a screw and a shaft accommodation hole for accommodating the shaft of the screw, which is continuous with the head accommodation hole. It is preferable that the hole and the cleaning unit communicate with the shaft portion accommodation hole . Further , it is preferable that a static elimination blower is attached to the air intake hole . Moreover, it is preferable that a communication hole through which a screw can pass and an exhaust hole intersecting the communication hole are formed in the transmission member. Furthermore, it is preferable that an exhaust filter is attached to the exhaust hole .

In the automatic screw tightening machine according to the present invention, since the chuck for receiving a screw is configured to be reciprocally movable from one end of the feeding member to the tip of the screw guide, the next screw is supplied during screw tightening. There are advantages such as being able to shorten the cycle time. In addition, the chuck is formed with a hanging hole for supporting the screw in a suspended manner, and the cleaning unit and the air intake hole communicate with the hanging hole. Therefore, when the cleaning unit is driven, external air can flow vigorously into the suspension hole. For this reason, there is also an advantage that the cleaning unit can efficiently collect deposits on the screws. In addition, since the chuck has a suspension hole consisting of a head housing hole and a shaft housing hole connected to the head housing hole, it is easier to machine than a pair of claws rotating symmetrically. There is also the advantage of being able to reduce costs related to dome production. In addition, since a filter is attached to the air intake hole and cleaned air flows into the suspension hole, there is an advantage that there is no risk of dust or the like adhering to the screw. Furthermore, when a static elimination blower is attached to the air intake hole, static electricity can be eliminated from the screw, and problems caused by static electricity during fastening of the substrate or the like can be prevented. Further, since the communicating member is formed with an exhaust hole, it is possible to reduce the load applied to the transfer means, which has the advantage of extending the life of the transfer means. Furthermore, since an exhaust filter is attached to the exhaust hole and the cleaned air can be exhausted, there is an advantage that the surroundings of the apparatus can be kept clean.

Claims (6)

A feed member through which a separately supplied screw can pass; a chuck having a suspension hole for receiving and supporting the screw ejected from one end of the feed member; a screw guide that can be pulled out by suction; a bit that is rotatably inserted through the screw guide and engages with the screw; In an automatic screw tightening machine equipped with transfer means for reciprocating movement,
An automatic screw tightening machine, wherein the suspension hole is connected to a cleaning unit that sucks air to collect deposits on the suspended screw and an intake hole that intersects with the suspension hole. The suspension hole is integrally provided with a head accommodation hole for accommodating the head of the screw and a shaft accommodation hole that is continuous with the head accommodation hole and accommodates the shaft of the screw,
2. The automatic screwdriver according to claim 1, wherein said intake hole and cleaning unit communicate with said shaft housing hole. 3. The automatic screwdriver according to claim 1, wherein an air intake filter is attached to an open end of said air intake hole. 3. The automatic screwdriver according to claim 1, wherein an antistatic blower is attached to the open end of the air intake hole. 5. The automatic screw tightening according to any one of claims 1 to 4, characterized in that a communicating hole through which a screw can pass and an exhaust hole intersecting the communicating hole are formed in said sending member. machine. 6. The automatic screwdriver according to claim 5, wherein an exhaust filter is attached to the open end of the exhaust hole.

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