JP3027975B2 - Connecting screw - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a connecting screw used in an automatic screw tightening machine, and more particularly, to a connecting screw which is securely supported by a connecting band by forming a knurl on a peripheral surface of a neck portion.

[0002]

2. Description of the Related Art As a connecting screw used in an automatic screw tightening machine, a shaft portion of a tapping screw is inserted into a support hole formed at a predetermined interval in a long connecting band formed by folding a wide sheet into a rectangular shape. Supported connecting screws are known.

In the connection screw of this configuration, the neck and the shaft between the screw head and the shaft are supported by being inserted into the support holes of the upper and lower pieces of the connection band, respectively. The surface of the shaft part is formed smoothly, and the neck part that is inserted into the support hole of the upper piece of the connection band is tapered so that the head side is large and the shaft part side is small, so that each screw is It is supported in such a state that it always comes off to the head side with respect to the support hole and is easily displaced. Therefore, if an external force is applied to the connecting screw by vibrating at the time of transportation or accidentally bringing the tip of the screw into contact with some member etc. at the time of loading into the automatic screw tightening machine,
The screw head moves in the direction away from the connection band,
If it is used as it is by loading it into an automatic screw tightening machine, it may cause poor feeding or clogging.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned disadvantages and to provide a connecting screw capable of reliably supporting a screw in a normal state with respect to a connecting band.

[0005]

In order to achieve the above object, a connecting screw according to the present invention is provided at a fixed interval on two opposing pieces of a long connecting band obtained by folding a wide sheet into a rectangular shape. A connecting screw for an automatic screw tightening machine in which a support hole is formed and a screw shaft is inserted into and supported by the corresponding support hole, and the entire peripheral surface of the neck between the head and the shaft of the screw has a shaft portion. The knurl along the longitudinal direction of the ridge, its peak protrudes from the peripheral surface of the neck,
The diameter of the knurled portion is reduced while the diameter of the head is large and the diameter gradually decreases toward the tip.
The diameter of the knurl is set to be larger than the diameter of the support hole of the connection band, and the length of the knurl in the screw axis direction is made substantially equal to the length between the two opposing pieces, so that the knurl is connected to the 2
It is characterized by being arranged and supported between the pieces.

[0006]

[Effect of invention the effect, according to the present invention, knurled screws are the mountain portion protrudes from the peripheral surface of the neck portion, the low
The diameter of the peak of the let is larger than the diameter of the support hole of the connecting band.
Is set between two opposing pieces of the connecting band.
Therefore , the screw is difficult to move in the axial direction with respect to the connection band. Therefore, even if external force is applied to the connecting screws due to vibration during transport or accidental contact of the tip of the screw with some member when loading the screw into the automatic screw tightening machine, each screw is positioned from the connecting band. It is possible to reliably support a normal state without shifting.

Further, the knurl is formed by reducing the diameter so that the head side has a large diameter and the diameter gradually decreases toward the tip end, so that the knurl is separated from the connecting band by pressing a driver bit of an automatic screw tightening machine. When the resistance is small,
Can be separated by a small pressing force.

Further, when the knurled portion is screwed into the screw-fastened member, the opening of the screw hole is further enlarged in diameter. For this reason, the screwing torque of the screw when the lower surface of the head enters the screw hole after the neck enters does not become so large. Therefore, the screw head can be sunk into the screw-fastened member without being reliably raised.

In addition, since a large torsion load as in the prior art is not applied to the screw shaft itself, the head of the screw is not torn off when the screw is tightened, and the screw hole is crushed. Nor.

[0010]

FIG. 1 shows a connecting screw according to the present invention. This connection screw is a connection screw for an automatic screw tightening machine, and is formed by inserting and supporting a screw 3 in a support hole 2 formed at a constant interval in the connection band 1.

The connecting band 1 is formed by folding a wide and long synthetic resin sheet into a rectangular shape and supporting upper and lower pieces 4 (duplicated) and a lower piece 5 facing each other vertically. A hole 2 is formed, a slit 6 is formed in the support hole 2 in a radial direction, and an engagement groove 7 is formed in shoulders on both sides.
The engagement groove 7 is for engaging with a claw (not shown) of a screw feed wheel of the automatic screw tightening machine and for screw feeding by rotation of the screw feed wheel.

As shown in FIGS. 2 and 3, the screw 3 has a head 3a, a shaft 3b, and a neck 3 between the head 3a and the shaft 3b.
c. A head groove 14 that engages with the driver bit is formed on the upper surface of the head 3a. Shaft 3b
A lead 8 is formed in the lower half of the lower part. Also, neck 3
The knurls 9 are formed on the entire peripheral surface of c.
The knurl 9 is formed along the longitudinal direction of the shaft portion 3b,
The peak portion 9a is formed so as to protrude stepwise from the peripheral surface of the neck portion 3c, and the outer diameter L1 is formed to be larger than the diameter L2 of the shaft portion 3b. The diameter is reduced so that the head 3a is large and the tip is small. Further, the length of the knurl 9 in the screw axis direction is formed so as to substantially match the length between the upper piece 4 and the lower piece 5 of the rectangular connecting band 1. Further, the diameter of the mountain portion 9a of the knurl 9 is
It is set to be larger than the diameter of the support hole 2 of the connecting band 1.
You.

Each of the screws 3 is inserted into the support hole 2 of the connecting band 1, and at this time, the knurls 9 are arranged between the upper piece 4 and the lower piece 5 of the connecting band 1. .

According to the connecting screw having the above configuration, the knurl 9 of the screw 3 has its crest 9a protruding from the peripheral surface of the neck 3c, and fits between the upper piece 4 and the lower piece 5 of the connecting band 1. Since the screws 3 are arranged in the mating state, the screws 3 are not easily moved in the axial direction with respect to the connecting band 1. Therefore, it may vibrate during transport,
When an external force is applied to the connecting screws by loading the screw 3 into the automatic screw tightening machine by accidentally bringing the tip of the screw 3 into contact with any member or the like, each screw 3 comes out of the connecting band 1 or rotates. Since displacement is unlikely to occur, it can be reliably supported in a normal state.

The knurl 9 is formed by reducing the diameter so that the head 3a has a large diameter and the diameter gradually decreases toward the distal end, so that the connecting band 1 is pressed by a driver bit of an automatic screw tightening machine. The resistance at the time of separation from the sheet is small, and it can be separated by a small pressing force.

Further, as shown in FIG. 4, a case in which a relatively hard decorative flooring material 11 is screwed on a relatively soft base material 10 will be described. When the knurl 9 is screwed into the flooring 11 while being screwed into the fastening material, the knurl 9 is larger than the diameter of the shaft portion 3b,
When the screw 3 is rotated, the diameter of the screw hole 12 formed by screwing is further increased by the knurl 9, and this portion becomes a so-called stupid hole. Moreover, the outer diameter of the knurl 9 is equal to the head 3a.
Since the diameter is reduced so that the side is large and the tip side is small, the shaft portion 3b enters like a cone when rotated. Thus, the screw hole 1 formed on the surface of the flooring 11
Since the diameter of the opening 2 is increased by the knurl 9, the resistance when the lower surface of the head 3a enters the screw hole 12 after the neck 3c enters is relatively small, and the screwing torque of the screw 3 is conventionally reduced. Since the screw 3 can be smaller, the screw tightening operation is easy and the head 3 of the screw 3
a can be reliably sunk without being lifted.

Moreover, since a large torsional load as in the prior art is not applied to the shaft 3b itself of the screw 3, the head 3a of the screw 3 may be torn off when the screw is tightened, and the screw hole may be crushed. Absent.

[Brief description of the drawings]

FIG. 1 is a perspective view of a connecting screw according to the present invention.

FIG. 2 is a sectional view of the connection screw.

FIG. 3 is a cross-sectional view of a knurled portion of the screw.

FIG. 4 is an explanatory view of a screw tightening mode using the screw.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Connecting band 3 Screw 3a Head 3b Shaft 3c Neck 4 Upper piece 5 Lower piece 9 Knurl 9a Mountain part

Continuation of front page (58) Field surveyed (Int.Cl. ⁷ , DB name) F16B 25/00-27/00

Claims (1)

(57) [Claims] 1. A support hole is formed at a predetermined interval in two opposing pieces of a long connecting band obtained by folding a wide sheet into a rectangular shape, and a shaft portion of a screw is inserted and supported in the corresponding support hole. With a connection screw for an automatic screw tightening machine, a knurl along the longitudinal direction of the shaft portion on the entire peripheral surface of the neck portion between the head portion of the screw and the shaft portion, the peak portion of which protrudes from the peripheral surface of the neck portion, and with head side can be formed by reducing the diameter to be gradually smaller in diameter toward the distal end side large diameter, Loule
The diameter of the peak of the socket is larger than the diameter of the support hole in the connection zone.
And connecting the knurl between the two pieces of the connecting band and supporting the knurl with the length of the knurl in the screw axis direction substantially equal to the length between the two opposing pieces. screw.