JPH0466653B2 - - Google Patents

Description

[Detailed description of the invention] (a) Industrial application field The present invention relates to an automatic horizontal screw driver, and more particularly, to an automatic horizontal screw driver that can hold screws in a stable state and perform accurate screw tightening. Regarding.

(B) Prior art In general, this type of automatic horizontal screw tightening machine, as shown in FIG. The base end of a vacuum pipe a is slidably inserted, and a bit f of a driver e is coaxially fitted and rotatably inserted into a case d, a vacuum pipe a, and a suction pipe b.
Then, the screw h stored in the hopper g is guided to the shooter j by the swinging action of the swinging blade i,
The screw h set in the catcher 1 is vacuum-adsorbed into the suction pipe b through the swingably attached escape k, and the head engagement groove of the screw h is engaged with the tip of the bit f, and the catcher is 1 as shown in the imaginary line, attach the suction pipe b to the object m to be fastened.
By pressing the tip end face of the screwdriver e, the driver e rotates and the screw h is screwed into the fastened body m.

However, the shape of the screw that can be accurately tightened using this type of automatic horizontal screw tightening machine is L/D > 1.0.
(L: dimension under the screw neck, D: diameter of the screw head). In other words, when L/D≦1.0, as shown in Fig. 5, the inclination of the screw h increases during vacuum suction, and the tip of the bit f does not engage accurately with the head engagement groove of the screw h, resulting in This had the disadvantage of inducing screw tightening errors. Furthermore, even if the tip of the bit f and the head engagement groove of the screw h are accurately engaged, the L/
If D≦1.0, the runout of the tip of the threaded portion becomes large during screw tightening operation, and the center deviation from the screw hole drilled in the fastened object m becomes large, resulting in the same screw tightening error as described above. There were flaws.

(c) Purpose The present invention solves these drawbacks and provides an automatic horizontal screw tightening machine that can hold screws horizontally by suction and reduce the vibration of the tip of the screw part during screw tightening operations, thereby allowing accurate screw tightening. The purpose is to

(D) Structure Therefore, the present invention is characterized in that the bit of the driver is coaxially inserted and rotatably inserted, and the suction pipe whose inside is maintained in a negative pressure state,
The distal end surface of a cylindrical float, which is close to the screw set in the catcher, is slidably fitted into the suction pipe, and whose distal end protrudes to the outside by the biasing force of the coil spring is fitted into the screw. The screw is held coaxially by suctioning the washer, and the negative pressure in the suction pipe overcomes the biasing force of the coil spring to retract the float, thereby storing the screw in the suction pipe, and , the tip of the bit engages with the engagement groove of the screw head to stop the screw from regressing, and at the same time induces a vacuum break between the tip surface of the float and the washer to stop the regress of the float. Then, with the screw held coaxially within the suction pipe, the tip of the suction pipe is brought into contact with the object to be fastened, and the screw is screwed into the screw hole of the fastening object as the bit rotates. The object to be fastened is fixed to the fastening body.

(E) Embodiment FIG. 1 shows the main parts of an automatic horizontal screw tightening machine according to the present invention.

In the figure, 1 is a suction pipe, which includes a cylindrical body 3 with an inner flange 2 formed on the inner peripheral surface near the tip (on the right side in the figure), and a proximal end side of the cylindrical body 3 (on the left side in the figure).
The suction pipe 1 is comprised of a cap 5 which is fitted into the cap 5 and has a threaded portion 4 projecting outward from the side of the cylindrical body 3.

A recess 8 in which a coil spring 7 is seated is provided in the fitting portion 6 of the cap 5, and a hole 9 communicating with the recess 8 is provided in the threaded portion 4. The bit 11 of the driver 10 is coaxially inserted into the suction pipe 1 through this hole 9 so as to be rotatable, and one end of the vacuum pipe 12 is screwed into the threaded part 4 as shown in the imaginary line. The interior of the suction pipe 1 is maintained in a negative pressure state by a vacuum source.

Reference numeral 13 denotes a cylindrical float that is slidably fitted into the suction pipe 1, and the tip of the float 13 is moved by the biasing force of the coil spring 7 interposed between the float 13 and the cap 5. protrudes outward from the end surface of the suction pipe 1. The base end of the float 13 is connected to the inner flange 2 of the suction pipe 1.
An outer flange portion 14 that engages with the outer flange portion 1 is provided in a protruding manner, and as shown in the figure, the outer flange portion 1
4 engages with the inner flange 2 to regulate the protrusion dimension of the float 13. Screw tightening is performed using the automatic horizontal screw tightening machine configured in this manner.

15 is a catcher into which a screw 16 is set as in FIG. In addition, a washer 17 is attached to the screw 16.
is fitted into the washer 17, and the tip surface of the float 13 comes into contact with this washer 17. The screw 16 is a so-called cross-recessed screw having a cross-shaped engagement groove 19 in the head 18.

Next, an example of use of the automatic horizontal screw tightening machine according to the present invention will be explained based on FIGS. 1 to 3.

(1) Attach the screw 16 set in the catcher 15,
The suction pipe 1 whose interior is kept in a negative pressure state is brought close together with the driver 10, and the washer 17 is suctioned to the tip surface of the float 13. In this state, the screw 16 is coaxially held on the float 13 (see FIG. 1). Note that the bit 11 of the driver 10 is rotating at a predetermined position.

(2) From this state, when the inside of the suction pipe 1 is further vacuumed, the negative pressure inside the suction pipe 1 overcomes the biasing force of the coil spring 7 and the float 13
is retracted, and the screw 16 is housed in the suction pipe 1 while being coaxially held. When the tip of the bit 11 engages with the engagement groove 19 of the screw head 18, the screw 16 stops retracting, but the float 13 continues retracting. In detail, screw 1
6 has stopped regressing, while the float continues to regress, a gap is created between the tip surfaces of the washer 17 and the float 13, a vacuum break occurs, and the negative pressure inside the suction pipe 1 decreases. . However, at that moment, the suction pipe 1 moves forward due to the biasing force of the coil spring 7, and as a result, the washer 17 is kept in close contact with the tip end surface of the float 13 at all times. Therefore, screw 16
are stably held coaxially at a predetermined position within the suction pipe 1 (see FIG. 2).

(3) Next, as shown in FIG. 3, when the tip of the suction pipe 1 is brought into contact with the object to be fastened 20 and the bit 11 is rotated, the screw 16 is screwed into the screw hole 22 of the object to be fastened 21. However, the object to be fastened 20 is the fastened object 21
Fixed.

Note that the present invention is not limited to the illustrated embodiments,
For example, it can be applied to screws with built-in washers (SEMS screws) and screws with flanges, or it can be applied to screws with different engagement grooves 19 in the screw heads 18, such as flathead screws or screws with hexagonal holes.

(F) Effect The present invention provides a suction pipe in which the bit of a driver is coaxially fitted and rotatably inserted, and the inside of which is maintained in a negative pressure state, and a coil spring that is slidably fitted into the suction pipe. a cylindrical float whose tip protrudes outward due to the biasing force of the float;
Since the washer fitted into the screw is adsorbed on the tip of the float, the screw can be held coaxially without tilting like in the conventional case, and the tip of the bit can be accurately placed in the engagement groove of the screw head. This can prevent screw tightening errors. Further, even if the shape of the screw is L/D≦1.0, the tip of the threaded portion does not run out easily during the screw tightening operation, and the screw can be tightened accurately. Therefore, it is fully applicable to screw tightening work of precision parts. Further, even when the screw tightening direction is diagonal or upward, the screw can be tightened accurately.

[Brief explanation of the drawing]

FIG. 1 is an enlarged cross-sectional side view of the main part showing an embodiment of the present invention, FIG. 2 is an enlarged cross-sectional side view of the main part showing the suction state, and FIG. 3 is an enlarged cross-sectional side view of the main part showing the screw tightening state. Figure 4 is an explanatory diagram showing a conventional usage example, Figure 5
The figure is an enlarged cross-sectional side view of a main part showing a conventional suction state. 1...Adsorption pipe, 7...Coil spring, 10
...Driver, 11...Bit, 13...Float, 1
5... Catcher, 16... Screw, 17... Washer,
18... Head, 19... Engagement groove, 20... Fastened body, 2
1... Fastening body, 22... Screw hole.

Claims (1)

[Claims] 1. An adsorption pipe whose interior is maintained in a negative pressure state;
The bit of the driver is rotatably fitted coaxially into the suction pipe, and the washer, which is slidably fitted inside the tip of the suction pipe and fitted onto the screw, is held by suction, and the negative pressure inside the suction pipe is The bit is equipped with a cylindrical float that retreats as the pressure increases, and a coil spring that is installed in the suction pipe and biases the float in a direction in which the tip surface of the float protrudes to the outside, and the bit is constantly rotated. It is configured so that it does not move forward or backward until it engages with the engagement groove of the screw head, but moves forward after it engages, and when the washer comes into contact with the tip of the float, the vacuum of the suction pipe is reduced. An automatic horizontal screw tightening machine characterized by being configured so that a pressure state is maintained.