JPH10131930A - Combination of +/-screw and driver bit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively prevent a come-out phenomenon of a driver bit and prevent a screw from being damaged, by changing a constitution of a groove part in a bit fitting groove of the screw, in combination of a +/- screw and the driver bit. SOLUTION: In a +/- screw 30, in a screw head part 30a, a bit fitting groove 32 formed by a cross groove is provided, one linear groove 32a with this bit fitting groove crossing is formed so as to fit conform a blade part of a + driver bit, also the other linear groove 32b is formed so as to fit conform a blade part of a - driver bit. Here, in an end edge part of one linear groove 32a fit conforming the blade part of the + driver bit, an almost vertical end wall part 33a of prescribed depth is formed, in the case of fitting a blade part tip end of the + driver bit to the bit fitting groove 32, this constitution is formed so as to fit to one linear groove 32a also so as to bring a lower edge part into contact with a groove bottom part 33b.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a screw provided with a bit fitting groove adapted to a plus screwdriver bit and a minus screwdriver bit, respectively, and a driver bit applied to the screw. A plumbing screw which can tightly fit a bit fitting groove formed of a cross groove to be formed and a driver bit adapted to the bit fitting groove, and can quickly and surely achieve screw mounting and removal by proper torque transmission. This relates to a combination with a driver bit.

[0002]

2. Description of the Related Art Conventionally, as a screw provided with a fitting groove adapted to a plus screwdriver bit and a minus screwdriver bit, for example, a Plumai screw 10 shown in FIGS. 11 and 12 is known. As a driver bit applicable to such a plastic screw, a Phillips screwdriver bit 20 configured as shown in FIG. 13 is used. FIG. 14 shows the plastic screw 10 and the Phillips screwdriver bit 20.
FIG.

[0003] The plastic screw 10 has an advantage that a conventionally known general screwdriver bit can be used.

However, the conventional plastic screw 10 shown in FIGS. 11 and 12 is provided with a fitting groove 12 formed of a cross groove on the screw head 10a. The fitting groove 12 is composed of a pair of straight grooves 10a and 10b crossing each other in a cross shape at the center of the screw head 10a, and one of the straight grooves 10a is brought into contact with the blade portion of the Phillips screwdriver bit. And the other straight groove 10b is configured to be in contact with the blade portion of the flathead screwdriver bit.

[0005] The one straight groove 12a is formed to extend from the edge to the center of the screw neck 10b as a fixed inclined groove (12a).
The bottom has a configuration in which a gently inclined substantially conical bottom surface 14 is formed. Tapered side walls 13a each having a taper toward the bottom are formed on both side surfaces of the inclined groove portion (12a), and the tapered side walls 13a abut and engage with the blade portion of a plus driver bit described later. I do.

The other straight groove 12b is formed to extend as a horizontal groove (12b) having a width and a depth sufficient to be brought into contact with the blade of the flathead screwdriver bit. On both side surfaces of the horizontal groove portion (12b), vertical side wall portions 13b substantially perpendicular to the bottom are formed, and the vertical side wall portions 13b abut and engage with the blade portions of the well-known minus driver bit. I do.

The one straight groove (inclined groove) 12
a at the even angle portion between the adjacent straight groove (horizontal groove portion) 12b and the other linear groove (horizontal groove portion) 12b.
b is formed, and a part of the blade portion of the driver bit, which will be described later, is also in contact with the tapered coupling surfaces 17a and 17b.

Therefore, the conventional Phillips screwdriver bit 20 shown in FIG.
Each of the blade portions 22 is fitted to the screw groove 10 and extends from the edge of the fitting groove 12 toward the center of the screw neck portion 10b so as to conform to the shape of the inclined groove portion 12a. The extended blade portion 22a is formed. Reference numeral 23 denotes tapered side wall portions formed on both side surfaces of each blade portion 22 or the extended blade portion 22a. That is, the tapered side wall portion 23 is formed as one straight groove (inclined groove portion) of the fitting groove 12 of the plastic screw 10 described above.
Abuts and engages with the tapered side wall portion 13a formed on 12a.

According to the conventional combination of a plastic screw and a Phillips screwdriver bit configured as described above, FIG.
When the plastic screw 10 and the Phillips screwdriver bit 20 are fitted together, as shown in FIG.
Are respectively fitted into the fitting grooves 12, and one of the pair of blade portions 22 and the side wall portion 23 of the extension blade portion 22 a are tapered side wall portions 13 a formed in one of the straight grooves (inclined groove portions) 12 a of the plastic screw 10. Abut. Thus, a predetermined torque can be transmitted to the plastic screw 10 by rotating the plus screwdriver bit 20. That is, it is possible to mount or remove the plastic screw 10 on a required screw mounting object.

[0010]

However, according to the combination of the conventional plastic screw 10 and the Phillips screwdriver bit 20 having the above-described structure, as shown in FIG. 14, one straight groove 12a in the screw head 10a is provided. Has a fixed inclined groove portion 12a which is directed toward the center of the screw neck portion 10b from the end edge thereof, while the corresponding Phillips screwdriver bit 20 has a ridge line portion of the extension blade portion 22a. The elongated groove portion 12a is fitted into the fitting groove 12 in conformity with the shape of the inclined groove portion 12a, and the ridge portion of the extended blade portion 22a is formed gradually wider toward the rear from the tip. Furthermore, the blade 2 of the Phillips screwdriver bit 20
The tapered side wall portion 23 formed on the screw 2 is also used for the plastic screw 10.
The positive screwdriver bit 20 is engaged with the tapered side wall portion 13a formed in the inclined groove portion 12a.
When the screwdriver is rotated in a predetermined direction, the contact state between the plus driver bit 20 and the inclined groove portion 12a can be said to be a taper contact on the entire surface. (Shown by arrows in FIG. 14), a so-called come-out phenomenon occurs.

Particularly, as shown in FIG. 12, the shape of the conventional fitting groove of the plastic screw facilitates the fitting of the tip blade portion of the driver bit. The width of the ridge portion of the extended blade portion 22a of the driver bit 20 is relatively large, while the tapered side wall portion 13a formed at the boundary portion between the crossing straight grooves 12a and 12b or at an even angle portion; The area of the portion 13b and the tapered coupling surfaces 17a, 17b are relatively small. Therefore, when the driver bit 20 is rotated, a large amount of stress is applied to the tapered side wall portion 13a, the vertical side wall portion 13b, and the tapered connecting surfaces 17a and 17b. 12, the tapered side wall 13a, the vertical side wall 13b, and the tapered connecting surfaces 17a and 17b are gradually damaged. Therefore, when the damaged portion (15) is enlarged, the cam-out phenomenon of the driver bit 20 becomes frequent, and finally the screw tightening operation becomes impossible.

From such a viewpoint, in order to prevent the cam-out phenomenon of the driver bit 20, when the driver bit 20 is rotated, it is necessary to apply a thrust for strongly pressing the driver bit 20 against the fitting groove 12 of the screw. Required. However, there is no problem when the mounting object of the screw is a rigid body such as a metal, but in the case of a precision part or the like,
There is a disadvantage that these objects are damaged or broken.

[0013] The occurrence of the above-mentioned come-out phenomenon is as follows.
The wear of the bit tip portion, that is, the blade portion 22 and the extension blade portion 22a is accelerated, and the wear further promotes the occurrence of the cam-out phenomenon. As a result, the damage of the fitting groove 12 of the screw increases.

Further, by applying an excessive thrust to the driver bit 20, it is possible to prevent the cam-out phenomenon, but on the other hand, it is possible to transmit an accurate torque to the screw. However, the magnitude of the thrust applied to the driver bit 20 differs depending on the operator, and as a result, there is a problem that the tightening torque of the screw varies.

Further, in the case of a tapping screw, when the screw is tightened to an object such as a synthetic resin, friction due to thrust is applied in addition to rotational friction of the screw, so that high heat is applied to the object. There is a problem in that the hardness of the screw mounting portion of the object is reduced due to the occurrence, and the loosening of the screw occurs or the object is damaged.

On the other hand, when the screw is manually tightened, the operation of rotating the screwdriver bit 20 while sufficiently pressing it against the screw has a disadvantage that it causes a great deal of labor and fatigue for the operator.

Further, according to the above-mentioned combination of the Brahmi screw 10 and the driver bit 20, when the screw is attached by using a manual tool or an electric tool, the bit tip portion with respect to the fitting groove of the screw is required. It is difficult to rotate the screw while maintaining the screw shaft and the driver bit shaft coaxially matched during the fitting of the screw shaft. Therefore, when the screw shaft and the driver bit shaft are inclined, In this case, not only the cam-out phenomenon frequently occurs but also the thread groove is frequently damaged.

Further, when removing the screw, the same cam-out phenomenon and the damage of the screw groove as described above are likely to occur, but in this case, the screw cannot be removed.
A situation arises in which a part of the mounting object of the screw must be destroyed. In particular, there is a drawback that when the dust is clogged in the fitting groove of the screw, the above-mentioned situation becomes remarkable.

Accordingly, an object of the present invention is to improve the configuration of the groove in the bit fitting groove of the screw in the combination of the plastic screw and the driver bit, thereby effectively preventing the cam out phenomenon of the driver bit. Screw and driver bit that can prevent proper screw breakage and always achieve proper and quick screw tightening work even if breakage occurs in the screw bit fitting groove part, significantly improving work efficiency And to provide a combination.

[0020]

In order to achieve the above object, a plastic screw according to the present invention is provided with a bit fitting groove formed of a cruciform groove in a screw head, and one of the straight lines intersecting the bit fitting groove. In the case of a plastic screw having a groove formed so that a blade portion of a Phillips screwdriver bit is fitted and fitted, and the other straight groove formed so that a blade portion of a minus driver bit is fitted and fitted, the blade of the Phillips screwdriver bit A substantially vertical end wall portion having a predetermined depth is formed at the edge of one of the straight grooves into which the portion fits, and the one straight line is fitted when the tip of the blade portion of the Phillips screwdriver bit and the bit fitting groove are fitted. A bit fitting groove is formed so as to fit into a groove and to fit a driver bit having a blade portion configured such that a lower edge portion thereof is in contact with the groove bottom portion.

In this case, the groove bottom of one of the straight grooves into which the blade portion of the Phillips screwdriver bit fits is directed toward the center of the screw head from the lower edge of the vertical end wall formed at the edge. It is possible to form an inclined groove portion extending toward the center portion of the screw neck portion further from the horizontal bottom portion, and to form a substantially conical bottom surface at the center bottom portion.

The groove bottom of the one straight groove is formed as a non-planar bottom protruding from the lower edge of the vertical end wall formed at the edge to the center of the screw head. It is also possible to form an inclined groove portion from the raised portion of the non-planar bottom toward the center of the screw neck, and to form a substantially conical bottom at the center bottom.

Further, the groove bottom of the one straight groove is formed as an inclined bottom inclined downward from the lower edge of the vertical end wall formed at the edge to the center of the screw head. Alternatively, a substantially conical bottom surface may be formed at the center bottom.

Further, the bit fitting groove into which the blade portion of the Phillips screwdriver bit fits is formed by forming one linear groove as a substantially divergent groove, and the groove width of the other linear groove is substantially divergent. It is also possible to form each of the grooves so that the blade portion of the Phillips screwdriver bit simultaneously contacts each side wall portion of the divergent groove with uniform clearance.

On the other hand, the driver bit adapted to the plastic screw has a flat blade portion having a substantially vertical edge fitted at the tip thereof along the vertical end wall of one straight groove of the screw head, It is characterized in that the tip surface of the blade portion is substantially horizontal and a projection is provided at the center thereof.

In the case where the bit fitting grooves of the plastic screw are formed as substantially divergent grooves, a driver bit adapted to the plastic screw is formed by fitting both side walls at the tip of the flat blade portion with the bit fitting of the plastic screw. It is preferable that the groove is formed in a shape compatible with the substantially divergent groove that forms the mating groove.

In the above-mentioned driver bit, it is preferable that both edges of the flat blade portion are formed at an acute angle by protruding an edge crossing the horizontal surface portion at the tip of the blade portion at a right angle or slightly toward the horizontal surface side. .

Further, in the driver bit,
A protrusion formed at the center of the horizontal tip surface of the flat blade portion,
It is preferable to form the plug into a shape that fits into the inclined groove formed in the center of the bit fitting groove of the plastic screw and the bottom surface of the cone.

According to the plastic screw according to the present invention, the edge of the bit fitting groove formed of one straight groove of the screw head is
By forming a substantially vertical end wall portion having a predetermined depth, the taper contact area with the one linear groove is partially and reduced when the tip of the blade portion of the Phillips screwdriver bit and the bit fitting groove are fitted. In addition, since the bottom of the bit fitting groove is provided so as to enlarge the area of the side wall portion with which the tip of the driver bit contacts, the cam-out phenomenon of the driver bit can be reliably prevented.

[0030] The driver bit according to the present invention comprises:
A flat blade portion having a substantially vertical edge portion fitted along a vertical end wall portion of a bit fitting groove formed of one of the straight grooves of the screw head at the distal end portion is provided, and the distal end surface of the blade portion is substantially horizontal. In addition, by adopting a configuration in which a projection is provided at the center thereof, it is possible to obtain a screw most suitable for the plastic screw.

Moreover, the plastic screw according to the present invention can be easily manufactured by using a header punch provided with a projection and a ridge adapted to the shape of each of the bit fitting grooves, particularly the shape of one of the linear grooves. Can be manufactured.

[0032]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing a combination of a screw and a driver bit according to the present invention.

FIGS. 1 and 2 show one embodiment of the plastic screw according to the present invention. That is, in FIGS. 1 and 2, reference numeral 30 indicates a plastic screw according to the present invention.
A bit fitting groove 32 is provided. The bit fitting groove 32 is formed by a pair of straight grooves 32a and 32b that cross each other at the center of the screw head 30a.

However, in the bit fitting groove 32 of the present embodiment, the one straight groove 32a forms a vertical end wall 33a having a predetermined depth at the edge thereof.
The groove bottom 33b extending from the lower edge 33a 'of the 3a toward the center of the screw head 30a forms a horizontal bottom and then from this horizontal bottom (33b) to the center of the screw neck 30b. To form the inclined grooves 33c respectively,
It has a configuration in which a slightly inclined substantially conical bottom surface 34 is formed at the center bottom. On both side surfaces of the straight groove 32a, substantially vertical side wall portions 3 of about 1.5 ° to 2 ° are formed, respectively, as a draft taper (the angle at which the header punch is pulled out).
5a is formed, and in this side wall portion 35a, abuts and engages with a side wall portion of a blade portion of a Phillips screwdriver bit described later.

The other straight groove 32b is formed to extend as a horizontal groove (32b) having a width and a depth sufficient to be brought into contact with the blade of the flathead screwdriver bit. On both side surfaces of the horizontal groove (32b), as in the case of the one straight groove 32a, a taper (pulling angle of the header punch) of about 1.5 ° to 2 ° is appropriately set.
A substantially vertical side wall portion 35b is formed, and the side wall portion 35b abuts and engages with a blade portion of a known flathead screwdriver bit.

It is to be noted that, at an even angle portion between the one linear groove 32a and the adjacent linear groove (horizontal groove) 32b,
As in the case of the conventional plastic screw shown in FIG. 12, required tapered connecting surfaces 37a and 37b are formed, respectively.

As described above, the plastic screw 30 in this embodiment has the vertical end wall 33a formed at the edge of one straight groove 32a of the screw head 30a and the groove bottom 33.
b is formed as horizontal bottom portions 33b, and the inclined groove portions 33c are formed to extend from these horizontal bottom portions 33b toward the center of the screw neck portion 30b so that the taper contact area with respect to the entire bit fitting groove 32 is reduced. The area of the side wall portion 35a which is partially and reduced in size and in which the tip of the driver bit abuts against one of the linear grooves 32a of the bit fitting grooves 32 facing each other. That is, the area of the driving surface)
Can be expanded.

The width of the one straight groove 32a is
Although it is configured so as to be adapted to the thickness of the blade portion of the driver bit described later, it is preferable that the configuration is slightly wider than the thickness in consideration of plating coating on the screw surface.

FIG. 3 shows a modification of the plastic screw 30 shown in FIG. 1 and FIG. That is, in this embodiment, one straight groove 32 of the bit fitting groove 32 is used.
The lower end 33a 'of the vertical end wall 33a having a predetermined depth formed on the end of the groove bottom 33b is formed with a screw head 30.
Non-planar bottom (33b) raised toward the center of a
Then, an inclined groove portion 33c is formed from the non-planar bottom portion (33b) toward the center of the screw neck portion 30b, and the center bottom portion is formed as a slightly inclined substantially conical bottom surface 34. It is. Other configurations are the same as those of the plastic screw 30 of the above embodiment.

In the thus-configured plastic screw 30 of the present embodiment, similarly to the above-described embodiment, the taper contact area with respect to the entire bit fitting groove 32 is partially and reduced, and the bit fitting opposed to the bit fitting groove 32 is formed. The area of the side wall 35a with which the tip of the driver bit abuts on one of the straight grooves 32a of the mating groove 32 can be enlarged.

FIGS. 4 and 5 show still another embodiment of the plastic screw according to the present invention. That is,
In the present embodiment, the groove bottom 33b of one of the linear grooves 32a of the bit fitting groove 32 is formed with a screw head from the lower edge 33a 'of the vertical end wall 33a having a predetermined depth formed at the edge thereof. 30a is inclined toward the center of the base 30a, and the bottom (33)
b), the central bottom of which is formed in a substantially conical bottom surface 3 having a gentle inclination.
4. Other configurations are the same as those of the plastic screw 30 of the above embodiment.

In the thus-configured plastic screw 30 of this embodiment, similarly to the above-described embodiment, the taper contact area with respect to the entire bit fitting groove 32 is partially and reduced, and the bit fitting of the opposite bit fitting groove 32 is performed. The area of the side wall 35a with which the tip of the driver bit abuts on one of the straight grooves 32a of the mating groove 32 can be enlarged.

FIG. 6 shows a plastic screw 3 according to the embodiment.
5 shows an embodiment of a driver bit 40 conforming to 0. That is, the driver bit 40 of the present embodiment is
Is fitted into the bit fitting groove 32 of the screw 30 and engages with the vertical end wall 33a and the groove bottom 33b formed at the edge of one linear groove 32a of the bit fitting groove 32, respectively. A flat blade portion 42 having a horizontal surface portion 43a extending substantially at a right angle is provided, and conforms to the shape of the inclined groove portion 33c formed from the groove bottom portion 33b of the straight groove 32a toward the center of the screw neck portion 30b. So that each of the projections 43b is projected.

Reference numeral 45 denotes each of the flat blade portions 4.
2 shows a substantially vertical side wall portion formed on both side surfaces of the second or horizontal plane portion 43a and capable of allowing a slight taper. Therefore,
The side wall portion 45 abuts and engages with the side wall portion 35a formed in the one linear groove 32a of the bit fitting groove 32 of the plastic screw 30 in the above-described embodiment. Therefore, since the engagement area of these drive surfaces can obtain a sufficiently large engagement area, it is possible to effectively prevent the cam-out phenomenon that has occurred in the conventional combination of the plamai screw and the driver bit. Become.

Also, in the plastic screw 30 in the above-described embodiment, the tapered connecting surfaces 37a and 37b are formed on the even-angle portions of the linear grooves 32a and 32b adjacent to the bit fitting groove 32, similarly to the conventional plastic screw. Due to the formation, even when a conventional driver bit as shown in FIG.
In 7a and 37b, a part of the blade portion of the driver bit is abutted and connected to achieve the screw tightening operation.

FIG. 7 shows a modified example of the driver bit 40 shown in FIG. 6, and the both ends 43a 'of the flat blade portion 42 in the driver bit 40 of the embodiment.
In this, the edge of the blade tip that intersects with the horizontal surface 43a is formed at an acute angle by projecting from a right angle toward the horizontal surface 43a, and the projection 43b is configured as a vertical projection 43c extending vertically downward. is there. That is, in the driver bit 40 of the present embodiment, the vertical projection 4
By forming 3c, this portion is configured so as not to make taper contact with the inclined groove portion 33c of the one linear groove 32a of the plastic screw 30 in the above-described embodiment. By configuring the driver bit 40 in this manner, the prevention of the cam-out phenomenon is further ensured.

FIG. 8 shows a plastic screw 3 according to the embodiment.
0 (see FIG. 3) and a fitting operation of the driver bit 40 (see FIG. 6). That is, according to the present embodiment, the horizontal surface portion 43a and the protrusion 43b formed on the flat blade portion 42 of the driver bit 40 fit into the groove bottom portion 33b and the inclined groove portion 33c of the one straight groove 32a of the plastic screw 30 respectively. Then, each of the blade portions 42 and the side wall portion 45 of the projection 43 b are connected to the one straight groove 3
2a can be brought into contact with the side wall 35a (see FIG. 9). Therefore, as shown in FIG.
By rotating 0 in the direction indicated by the arrow, the abutting portion (T1, T2) between the blade portion 42 of the driver bit 40 and one of the linear grooves 32a of the plamai screw 30 is
A predetermined torque can be transmitted to the plastic screw 30. In this case, in the relationship between the other linear groove 32b of the plastic screw 30 and the blade portion 42 of the driver bit 40, the blade portion 42 is connected to the other linear groove 32b.
b cannot contact the side wall 35b (T3, T4) (see FIG. 9).

In particular, according to this embodiment, the plastic screw 3
In the case where the non-planar bottom portion 33b is formed in one of the linear grooves 32a of the bit fitting groove 32 of 0, the flat blade portion 42 of the driver bit 40 is used for fitting with the driver bit 40.
The contact area of the side wall portion 35a contacting the side wall portion 45 can be increased, and at the same time, the inclined groove portion 33c of the one straight groove 32a of the plastic screw 30 and the driver bit 4
Since the tapered contact area where the zero protrusion 43b abuts is partial and small, it is possible to reliably prevent the cam-out phenomenon that has occurred in the conventional combination of the plamai screw and the driver bit (see FIG. 8).

FIG. 10 shows a plastic screw 30 according to the present invention.
This shows still another embodiment of the present invention. That is, in this embodiment, one straight groove 32 of the plastic screw 30 is used.
a and the other linear groove 32b are formed such that the groove widths become substantially divergent grooves 32a 'and 32b', respectively, in correspondence with the blade portion 42 of the driver bit 40. Thus, the flared groove 32
By forming the a ′ and 32b ′, when the blade portion 42 of the driver bit 40 comes into contact with each side wall portion of the bit fitting groove 32 of the plastic screw 30, a uniform clearance δ is set as shown in FIG. And one groove 32
a 'can contact the side wall (T1, T2') of the other groove 32b 'simultaneously with the contact of the side wall (T1, T2) to achieve balanced torque transmission. Can be.

Therefore, according to the present embodiment, when the driver bit 40 is fitted into the bit fitting groove 32 of the plastic screw 30, the driver bit is attached to all four side walls of the fitting groove 32. The blades 42 of the blade 40 can be simultaneously contacted, and sufficient torque can be transmitted in the screwing operation of the plastic screw 30.

In this case, the flat bit is used as the driver bit 40 applied to the plastic screw 30 formed so that the bit width of the bit fitting groove 32 becomes substantially divergent grooves 32a 'and 32b'. The side wall portion 45 at the tip of the portion 42 is formed with the divergent groove 32 respectively.
a 'and 32b', a clearance δ as shown in the drawing is provided when the blade portion 42 of the driver bit 40 comes into contact with each side wall portion of the bit fitting groove 32 of the plastic screw 30. By solving the problem, it is possible to achieve appropriate bit fitting with the plastic screw.

The preferred embodiment of the present invention has been described above. However, the present invention is not limited to the above-described embodiment, and various design changes can be made without departing from the spirit of the present invention. It is.

[0053]

As is apparent from the above-described embodiment, the plastic screw according to the present invention has a bit fitting groove formed of a cross groove in the screw head, and one of the straight grooves intersecting the bit fitting groove. In a plastic screw having a blade portion of a Phillips screwdriver bit formed so that the blade portion of the Phillips screwdriver bit fits therein, and the other straight groove formed so that the blade portion of the flathead screwdriver bit fits therein. By forming a substantially vertical end wall portion of a predetermined depth at the edge of one of the linear grooves into which the fitting is fitted, when the leading end of the driver bit is fitted to the bit fitting groove, The taper contact area is partially and reduced, and the bottom of the bit fitting groove is provided so as to enlarge the area of the side wall with which the tip of the driver bit abuts. Ri, the come-out phenomenon of the driver bit can be reliably prevented.

Further, the driver bit according to the present invention
A flat blade portion having a substantially horizontal surface portion is provided at the tip thereof for engaging with a groove bottom formed at the edge of one of the straight grooves of the screw, and the tip portion of each of the blade portions extends from the groove bottom. By providing a projection formed so as to conform to the shape of the groove, it is possible to obtain the most suitable one for the plastic screw.

In the present invention, the use of a header punch provided with a projection or a ridge adapted to the shape of one of the straight grooves of the plastic screw allows mass production of the screw to be carried out simply and at low cost. can do.

In particular, the plastic screw according to the present invention, when forming the bit fitting groove in the screw head, is directed from the lower edge of the vertical end wall of one of the straight grooves toward the center of the screw head. In the case of forming the raised non-planar bottom, the raised non-planar bottom is formed by using the protrusions or ridges of the header punch. Even if it is slightly worn, there is no problem in forming the raised non-planar bottom portion, and therefore, an advantage is obtained that the production of the plastic screw according to the present invention can be mass-produced at low cost.

In the present invention, when forming the bit fitting groove of the screw head, it is preferable that one of the straight grooves is raised from the lower edge of the vertical end wall toward the center of the screw head. It is possible to manufacture a plastic screw having a structure in which the thickness at the time of forming the groove in the screw neck is appropriately maintained, and the strength at the time of tightening or removing the screw is sufficiently maintained.

The plastic screw according to the present invention basically has a configuration in which the tapered contact area with the entire bit fitting groove is partially and reduced when fitting with the driver bit, and the side wall portion at the tip of the driver bit. The area of the side wall of the bit fitting groove with which the
The cam-out phenomenon of the driver bit is almost eliminated, and this effect has an advantage that it can be effectively exerted even when a conventional driver bit configured as shown in FIG. 13 is used.

Therefore, the screw according to the present invention is, for example, shown in FIG.
Even if a driver bit as shown in FIG. 3 is used, a proper screw tightening operation can be achieved. However,
In this case, due to a cam-out phenomenon that occurs when a conventional driver bit is used, a part of the bit fitting groove is likely to be damaged (reference numeral 15) as shown in FIG. 12, for example. Then, when such damage occurs, it is no longer possible to tighten and remove the screw with the conventional driver bit.

However, according to the plastic screw according to the present invention, the driver bit according to the present invention can be used even when the above-described breakage occurs in a part of the bit fitting groove of the screw head. By doing so, it is possible to achieve a proper screw tightening operation and a screw removing operation without a cam-out phenomenon.

Further, according to the combination of the plastic screw and the driver bit according to the present invention, when the bit fitting groove of the screw becomes clogged or the like, or when the screw shaft and the bit shaft are not coaxial. However, the rotation of the driver bit can be smoothly transmitted to the Plumai screw without causing a cam-out phenomenon or breakage of the screw or the like, so that the screw tightening operation with an appropriate torque can always be promptly achieved.

That is, if the combination of the plastic screw and the driver bit according to the present invention is used, the screw is securely tightened with an appropriate torque on the object to be screwed, which is made of various hard and soft materials. Not only that, the breakage of the screw can be greatly reduced, and the safety of the screw tightening operation and the improvement of the work efficiency can be easily and economically achieved.

[Brief description of the drawings]

FIG. 1 is a plan view of a screw head showing an embodiment of a plastic screw according to the present invention.

FIG. 2 is a cross-sectional side view of a main part of the plastic screw shown in FIG. 1 along the line II-II.

FIG. 3 is a cross-sectional side view of a main part showing a modification of the plastic screw in FIG. 2;

FIG. 4 is a plan view of a screw head showing another embodiment of the plastic screw according to the present invention.

FIG. 5 is a cross-sectional side view of a VV line main part of the plastic screw shown in FIG. 4;

FIG. 6 is a side view of an essential part showing an embodiment of a driver bit suitable for a plastic screw according to the present invention.

FIG. 7 is a cross-sectional side view of a main part showing a modification of the driver bit shown in FIG. 6;

8 is a cross-sectional side view of a main part showing a connected state of the plastic screw shown in FIG. 3 and the driver bit shown in FIG. 6;

FIG. 9 is an explanatory plan view of a main part of the screw head, showing a coupled state of the driver bit shown in FIG. 6 in the plastic screw head shown in FIG. 1;

FIG. 10 is an explanatory plan view of a main part of a screw head, showing still another embodiment of the plastic screw according to the present invention.

FIG. 11 is a cross-sectional side view of a main part of a conventional plastic screw.

FIG. 12 is a plan view of the head of the plastic screw shown in FIG. 11;

FIG. 13 is a side view of a main part of a conventional Phillips screwdriver bit.

14 is a cross-sectional side view of a main part showing a coupling state of the plastic screw shown in FIG. 11 and the driver bit shown in FIG.

[Explanation of symbols]

 30 plastic screw 30a screw head 30b screw neck 32 bit fitting groove 32a linear groove 32b linear groove (horizontal groove) 32a ', 32b' divergent groove 33a vertical end wall 33a 'lower edge 33b groove bottom (horizontal) 33b 'Raised portion 33c Inclined groove portion 33d Taper 34 Conical bottom surface 35a Side wall portion (of one straight groove 32a) 35b Side wall portion (of the other straight groove 32b) 37a, 37b Taper coupling surface 40 Driver bit 42 Flat blade part 43a Horizontal plane part 43a 'Edge part 43b Projection 43c Vertical projection 45 Side wall part

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[Procedure amendment]

[Submission date] January 20, 1997

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0004

[Correction method] Change

[Correction contents]

However, the conventional plastic screw 10 shown in FIGS. 11 and 12 is provided with a fitting groove 12 formed of a cross groove on the screw head 10a. This fitting groove 12 consists of a pair of linear grooves 1 2 a, 1 2 b intersecting crosswise to each other at the center of the screw head 10a, while the linear grooves 1 2 a is a blade portion of the Phillips screwdriver bit together configured to abut fitting, the other linear groove 1 2 b is configured to blade portion abutting engagement screwdriver bit.

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0005

[Correction method] Change

[Correction contents]

The one straight groove 12a is formed as an inclined groove 12a which is inclined from the edge to the center of the screw neck 10b, and a gently inclined substantially conical bottom surface 14 is formed at the bottom. It consists of the configuration.
On both side surfaces of the inclined groove portion 12a , tapered side wall portions 13a each having a taper toward the bottom are formed, and the tapered side wall portions 13a abut and engage with the blade portion of a plus driver bit described later.

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0006

[Correction method] Change

[Correction contents]

[0006] The other straight groove 12b is formed to extend as a horizontal groove 12b having a width and depth sufficient to abut and engage the blade portion of the flathead screwdriver bit. Then, on both side surfaces of the horizontal groove portion 12b , vertical side wall portions 13b substantially perpendicular to the bottom are formed, and the vertical side wall portions 13b are in contact with and engaged with the blade portions of a well-known minus driver bit.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0007

[Correction method] Change

[Correction contents]

The one straight groove (inclined groove) 12
a and the other straight groove (horizontal groove) 12b adjacent thereto.
At the corners , the required tapered connecting surfaces 17a, 17
b is formed, and a part of the blade portion of the driver bit, which will be described later, is also in contact with the tapered coupling surfaces 17a and 17b.

[Procedure amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0008

[Correction method] Change

[Correction contents]

Therefore, the conventional Phillips screwdriver bit 20 shown in FIG.
Each of the blade portions 22 is fitted to the screw groove 10 and extends from the edge of the fitting groove 12 toward the center of the screw neck portion 10b so as to conform to the shape of the inclined groove portion 12a. The extended blade portion 22a is formed. Reference numeral 23 denotes tapered side wall portions formed on both side surfaces of each blade portion 22 or the extended blade portion 22a. That is, the tapered side wall portion 23 abuts and engages with the tapered side wall portion 13a formed in the one inclined groove portion 12a of the fitting groove 12 of the plastic screw 10 described above.

[Procedure amendment 6]

[Document name to be amended] Statement

[Correction target item name] 0009

[Correction method] Change

[Correction contents]

According to the conventional combination of a plastic screw and a Phillips screwdriver bit configured as described above, FIG.
When the plastic screw 10 and the Phillips screwdriver bit 20 are fitted together, as shown in FIG.
Are fitted in the fitting grooves 12, respectively, and the tapered side wall portions 23 of the pair of blade portions 22 and the extended blade portions 22a abut on the tapered side wall portions 13a formed in the one inclined groove portion 12a of the plastic screw 10. . Thus, a predetermined torque can be transmitted to the plastic screw 10 by rotating the plus screwdriver bit 20.
That is, it is possible to mount or remove the plastic screw 10 on a required screw mounting object.

[Procedure amendment 7]

[Document name to be amended] Statement

[Correction target item name] 0010

[Correction method] Change

[Correction contents]

[0010]

However, according to the combination of the conventional plastic screw 10 and the Phillips screwdriver bit 20 having the above-mentioned structure, as shown in FIG. 14, one inclined groove 12a in the screw head 10a. Is
A fixed inclined surface is formed from the edge to the center of the screw neck 10b, while the corresponding Phillips screwdriver bit 20 has a ridge line portion of the extended blade portion 22a and the inclined groove portion 12a. The fitting groove 12 conforms to the shape of
And the ridge portion of the extended blade portion 22a is
It is formed gradually wider toward the rear from the tip. Further, the tapered side wall portion 23 formed on the blade portion 22 of the Phillips screwdriver bit 20 also comes into contact with and engages with the tapered side wall portion 13a formed on the inclined groove portion 12a of the plastic screw 10. When turned in a predetermined direction, the Phillips screwdriver bit 2
0 and the inclined groove portion 12a can be said to be tapered contact on the entire surface.
The leading end of 0 tries to jump outward along the inclined surface of the inclined groove portion 12a (indicated by an arrow in FIG. 14), which causes a so-called cam-out phenomenon.

[Procedure amendment 8]

[Document name to be amended] Statement

[Correction target item name] 0011

[Correction method] Change

[Correction contents]

Particularly, as shown in FIG. 12, the shape of the conventional fitting groove of the plastic screw facilitates the fitting of the tip blade portion of the driver bit. is relatively larger than the width of the ridge line portion of the extension blade portion 22a of the driver bit 20, whereas the cross-shaped in exchange <br/> difference to the linear groove 12a, a tapered side wall to no boundary portion between 12b are formed on the corners The area of the portion 13a, the vertical side wall portion 13b, and the tapered coupling surfaces 17a, 17b are relatively small. Therefore, when the driver bit 20 is rotated, a large amount of stress is applied to the tapered side wall portion 13a, the vertical side wall portion 13b, and the tapered connecting surfaces 17a and 17b. 12, the tapered side wall 13a, the vertical side wall 13b, and the tapered connecting surfaces 17a and 17b are gradually damaged. Therefore, when the damaged portion (15) is enlarged, the cam-out phenomenon of the driver bit 20 becomes frequent, and finally the screw tightening operation becomes impossible.

[Procedure amendment 9]

[Document name to be amended] Statement

[Correction target item name] 0045

[Correction method] Change

[Correction contents]

Also, in the plastic screw 30 of the above-described embodiment, tapered connecting surfaces 37a and 37b are formed at the corners of the linear grooves 32a and 32b adjacent to the bit fitting groove 32, similarly to the conventional plastic screw. Due to the formation, even when a conventional driver bit as shown in FIG.
In 7a and 37b, a part of the blade portion of the driver bit is abutted and connected to achieve the screw tightening operation.

[Procedure amendment 10]

[Document name to be amended] Statement

[Correction target item name] 0049

[Correction method] Change

[Correction contents]

FIG. 10 shows a plastic screw 30 according to the present invention.
This shows still another embodiment of the present invention. That is, in this embodiment, one straight groove 32 of the plastic screw 30 is used.
a and the other linear groove 32b are formed such that the groove widths become substantially divergent grooves 32a 'and 32b', respectively, in correspondence with the blade portion 42 of the driver bit 40. Thus, the flared groove 32
By forming the a ′ and 32b ′, when the blade portion 42 of the driver bit 40 comes into contact with each side wall portion of the bit fitting groove 32 of the plastic screw 30, a uniform clearance δ is set as shown in FIG. And one groove 32
a 'can be simultaneously contacted with the side wall (T1, T2) of the other groove 32b' and simultaneously with the side wall ( T3, T4 ) of the other groove 32b ', so that a balanced torque transmission can be achieved. .

[Procedure amendment 11]

[Document name to be amended] Drawing

[Correction target item name] FIG.

[Correction method] Change

[Correction contents]

FIG. 14

Claims (9)

[Claims] 1. A bit fitting groove comprising a cruciform groove is provided in a screw head, and one straight groove intersecting the bit fitting groove is formed so that a blade portion of a Phillips screwdriver bit fits therein. The straight groove formed so that the blade portion of the minus driver bit fits into the fitting portion, wherein the edge portion of one of the linear grooves into which the blade portion of the plus driver bit fits has a predetermined depth. A substantially vertical end wall portion is formed so that when the tip of the blade portion of the Phillips screwdriver bit and the bit fitting groove are fitted, the one linear groove is fitted, and the lower edge portion abuts the groove bottom. A plumbing screw characterized in that a bit fitting groove is formed so as to fit a driver bit having a set blade portion. 2. The groove bottom of one of the straight grooves into which the blade portion of the Phillips screwdriver fits is directed toward the center of the screw head from the lower edge of the vertical end wall formed at the edge. 2. A plumbing machine according to claim 1, wherein said flat bottoms are formed as extended horizontal bottoms, and each of said inclined bottoms is formed further toward said center portion of said screw neck portion than said horizontal bottom portions, and a substantially conical bottom surface is formed at said center bottom portion. screw. 3. The groove bottom of one of the straight grooves, into which the blade of the Phillips screwdriver bit fits, is directed toward the center of the screw head from the lower edge of the vertical end wall formed at the edge. 2. The method according to claim 1, wherein the non-planar bottoms are formed as raised non-planar bottoms, and the non-planar bottoms are each formed with a slanting groove directed toward the center of the screw neck, and a substantially conical bottom surface is formed at the center bottom. The described plastic screw. 4. The groove bottom of one of the straight grooves into which the blade portion of the Phillips screwdriver fits is directed toward the center of the screw head from the lower edge of the vertical end wall formed at the edge thereof. 2. The plastic screw according to claim 1, wherein the screw is formed as a downwardly inclined inclined bottom, and a substantially conical bottom surface is formed at a central bottom thereof. 5. A bit fitting groove into which a blade portion of a Phillips screwdriver fits is formed by forming one of the linear grooves as a substantially divergent groove and having the groove width of the other linear groove substantially divergent. 2. The plastic screw according to claim 1, wherein each of the grooves is formed so that a blade portion of the Phillips screwdriver bit simultaneously contacts each side wall of the divergent groove with an equal clearance. 6. A flat blade portion having a substantially vertical edge portion which is fitted along a vertical end wall portion of one of the straight grooves of the screw head at a tip portion, and the tip surface of the blade portion is substantially horizontal. 5. A driver bit suitable for a plastic screw according to claim 1, wherein a projection is provided at a central portion thereof. 7. A flat blade portion according to claim 6, wherein both side wall portions at the distal end of said flat blade portion are formed in a shape which is compatible with a substantially divergent groove forming a bit fitting groove of said plastic screw. Driver bit. 8. The driver according to claim 6, wherein, at both edge portions of the flat blade portion, an edge crossing the horizontal surface portion at the tip of the blade portion is formed at a right angle or slightly toward the horizontal surface portion to form an acute angle. bit. 9. A projection formed at the center of the horizontal tip surface of the flat blade portion is formed as a cone with an inclined groove formed at the center of the bit fitting groove of the plastic screw according to any one of claims 2 to 5. 8. The driver bit according to claim 6, wherein the driver bit is configured to have a shape adapted to each of the bottom surfaces.