GB2256609A

GB2256609A - Screwdriver

Info

Publication number: GB2256609A
Application number: GB9112612A
Authority: GB
Inventors: Chuan-Wu Chen
Original assignee: Individual
Current assignee: Individual
Priority date: 1991-06-12
Filing date: 1991-06-12
Publication date: 1992-12-16
Anticipated expiration: 2011-06-12
Also published as: FR2676952B3; GB9112612D0; FR2676952A3; GB2256609B

Abstract

A screwdriver comprises a handle 12 with a tubular member 24 disposed therein. A first shank 26 is placed through the tubular member and is anchored at the bottom of the handle. A second shank 30 is pivotally fastened to the distal end of the first shank. A third shank 32 is pivotally coupled with the distal end of the second shank so that they can be arranged to be coaxial or perpendicular to each other. One end of a coil spring 33 surrounding the first shank 26 acts against the tubular member. When the first, second and third shanks are aligned coaxially, a straight screwdriver is formed. When the third shank is perpendicular to the second shank, an L-shaped screwdriver is formed. When the first and third shanks are separately perpendicular to the second shank, a Z-shaped screwdriver is formed. <IMAGE>

Description

SCREWDRIVER This invention relates to a screwdriver, and more particularly to a screwdriver designed with interchangeable straight shank, L-shaped shank, and Zshaped shank.

In general, a conventional screwdriver of the prior art comprises mainly a handle and a straight shank which is attached to the handle at one end thereof. Such a screwdriver is inherently limited in that it does not serve the purpose well in a situation calling for screws and the like to be tightened or loosened with a greater turning moment or at a fast pace.

According to the present invention, there is provided a screwdriver comprising an elongate handle having a proximal end and a distal end and having a receiving chamber along the long axis thereof, and a driver device attached to the handle, the driver device comprising: (a) a tubular member having proximal and distal ends and having a through hole along the axis thereof and being lodged in the receiving chamber in such a manner that the tubular member can move in a direction along the long axis of the handle and that the distal end region of the tubular member protrudes beyond the receiving chamber; (b) a first shank, having proximal and distal ends, disposed in the through hole of the tubular member and fixed at its proximal end region with respect to the proximal end region of the handle;; (c) a second shank, having proximal and distal ends, with the proximal end region being pivotally coupled to the distal end region of the first shank; (d) a third shank, having proximal and distal ends, with the proximal end region being fastened to the distal end region of the second shank in such a manner that it can be in a first position in which the third shank and second shank are perpendicular to each other or a second position in which the third shank and second shank are aligned with each other, and with the distal end region having a sleeve portion attached thereto; and (e) a biasing means associated with the tubular member in such a manner as to tend to urge the tubular member outwardly from the receiving chamber.

The sleeve portion of the third shank can in use be fitted over driver head tips of various shapes and sizes.

When the first, second and third shanks are aligned coaxially, a straight screwdriver is formed.

When the third shank is perpendicular to the second shank, an L-shaped screwdriver is formed. When the first and third shanks are separately perpendicular to the second shank, a Z-shaped screwdriver is formed.

Thus, the screwdriver of the present invention may provide a substantially straight shank and a generally L-shaped shank arranged interchangeably to facilitate the screwdriver to be used in a situation requiring screws to be tightened or loosened with a greater turning moment.

The screwdriver of the present invention may further provide a substantially straight shank and a generally Z-shaped shank arranged interchangeably to facilitate the screwdriver to be used to tighten or loosen the screw and the like at a high speed.

Furthermore, the screwdriver of the present invention may provide a substantially straight shank, a generally L-shaped shank, and a generally Z-shaped shank, which can be interchanged easily.

Preferably, the biasing means comprises a coil spring, having proximal and distal ends, around the first shank, with the proximal end region being lodged in the proximal end region of the receiving chamber and the distal end region being placed at the proximal end region of the tubular member.

The handle may comprise a tubular body which in turn comprises the hollow receiving chamber, a proximal end, a distal end, a substantially hemi-spherical bottom cover fastened to the proximal end region and a circular top cover having a central aperture and attached securely to the distal end region.

Preferably the tubular member comprises a flange near its proximal end region and a plurality of ribs located adajcent to the flange, and wherein the circular top cover comprises a plurality of grooves located on its inner wall surface and positioned correspondingly to the ribs for accommodating the ribs.

In a further preferred feature the tubular member is fastened to a ring sleeve at the distal end region, the ring sleeve having a ring shoulder disposed thereon.

The tubular body of the handle is provided at its proximal end with a through hole and with provision for securement of the substantially hemi-spherical bottom cover, and wherein a stopping sleeve is lodged at the proximal end region of the receiving chamber of the tubular body, the stopping sleeve comprising a circular recess, which in turn is provided with a non-circular recess seat, with a through hole disposed in the recess seat, with the coil spring lodged in the circular recess, with a a proximal axial extension of the first shank being lodged in the non-circular recess seat and passing through the through hole to extend beyond the proximal end of the tubular body for attachment to a generally C-shaped clamp piece and to the substantially hemi-spherical bottom cover, the first shank at least in its proximal end region, having a body of noncircular cross-section corresponding to the noncircular recess seat of the stopping sleeve.

Preferably, the first shank comprises a lug located at the distal end region, and the second shank is provided with a first groove located at the proximal end region, the first and second shanks being coupled by means of a pin traversing the side walls of the first groove and the lug.

Preferably, the second shank further comprises a second groove located at the distal end, the second groove having a recess hole which is located at the bottom wall thereof and containing therein a coil spring and a steel ball in that order; the third shank preferably comprises a second lug located at the proximal end, the second lug having a flat portion and, spaced therefrom, two recesses to the flat portion, one or other of the recesses serving to receive the steel ball when the third shank is in the first position.

For a better understanding of the present invention, and to show how the same may be carried into effect, reference will now be made, by way of example, to the accompanying drawings, in which: Figure 1 shows as exploded view of the preferred embodiment of screwdriver of the present invention; Figure 2 shows an external three-dimensional view of the preferred embodiment with the L-shaped shank disposed thereto according to the present invention; Figure 3 shows an enlarged sectional view taken along the direction indicated by line 3-3 as shown in Figure 2; Figure 4 shows an external three-dimensional view of the preferred embodiment with a straight shank disposed thereto according to the present invention; and Figure 5 shows an external three-dimensional view of the preferred embodiment with a Z-shaped shank disposed thereto according to the present invention.

Referring to Figures 1-5, the screwdriver 10 embodied in the present invention is shown comprising a handle 12 and a driver device 14 attached to the handle 12.

The handle 12 is composed of a long tubular body 13 which in turn consists of a hollow receiving chamber 15, distal open end 16, a proximal end 18, a substantially hemi-spherical bottom cover 20 fastened to the proximal end 18, and a circular top cover 22 having a central circular hole and attached securely to the distal end 16.

The driver device 14 comprises a long tubular member 24, a ring sleeve 25, a first shank 26, a second shank 30, a third shank 32, and a coil spring 33. The tubular member 24 is lodged in the receiving chamber 15 and extends through the circular hole of the top cover 22 at one end thereof. The ring sleeve 25 is fastened to the distal end region of the tubular member 24. The first shank 26 is lodged in the tubular member 24 in a manner that one end of the first shank 26 reaches the bottom portion of the receiving chamber 15 so as to engage with a stopping sleeve 28 located at the proximal end region 18. The second shank 30 is fastened, with a toggle, at its proximal end region to the distal end region of the first shank 26. In a similar manner, the third shank 32 is fastened, with a toggle, at its proximal end region to the distal end region of the second shank 30. The coil spring 33 is used to encase the first shank 26, having one end engaging with the stopping sleeve 28.

The tubular member 24 is provided with a flange 34 disposed at the proximal end located inside the receiving chamber 15. The flange 34 is used to prevent the tubular member 24 from escaping. In addition, the tubular member 24 is provided with a plurality of ribs 36, which are located adjacent to the flange 34 and are intended to engage grooves 38 located on the inner wall surface of the top cover 22 at the time when the tubular member 24 has reached its outer limit. Located on the inner wall surface of the ring sleeve 25 is a ring rib 40, which engages a ring groove 42 located near the distal end of the tubular member 24 so as to permit the ring sleeve 25 to be fastened securely to the tubular member 24. The ring sleeve 25 has a ring shoulder 44 perpendicular to the axis of the tubular member 24.

The first shank 26 is composed of a shank body 46 which has circular cross-section at its distal end region but which over the majority of its length is provided with two opposed flats giving a non-circular cross-section, a proximal axial extension 48 located at the proximal end region of the shank body 46, and a lug 50 located at the distal end region of the shank body 46. The extension 48 passes through a through hole 52 of the stopping sleeve 28 and the through hole 54 of the proximal end 18 so as to be located in a hole 56 of the bottom cover 20. A generally C-shaped clamp piece 58 is attached to the portion of the extension 48 which extends beyond the through hole 54. The non-circular shoulder 49 located at the junction of the column portion 48 and the shank body 46 is embedded in a noncircular recess 62 of stopping sleeve 28.The stopping sleeve 28 securely abuts the proximal end of the handle 12.

The non-circular portion of the tubular member 24 corresponds to the non-circular portion of the first shank 26. Rotation in the straight configuration of the screwdriver, when the first, second and third shanks are aligned coaxially, is imparted from the handle 12 to the first shank 26 through the ribs 36 engaging with the grooves 38 which causes rotation of the tubular member 24 and hence the first shank 26.

The second shank 30 comprises a first groove 64 and a first lock pin 66 at is proximal end region. The first groove 64 is used for receiving the lug 50 of the first shank 26 while the first lock pin 66 is used to traverse the side walls defining the first groove 64 and the lug 50 so as to couple the first shank 26 and the second shank 30 in the manner of a toggle. In addition, the second shank 30 comprises a second groove 68 at the distal end region. Opening into the bottom of the second groove 68 is a recess hole 70. The recess hole 70 is used to accommodate a coil spring 72 and a small steel ball 74 in that order.

The third shank 32 comprises a lug 76 at the proximal end region and a sleeve portion 78 at the distal end region. The lug 76 is lodged in the second groove 68 of the second shank 30 and is fastened to the second groove 68 in the manner of a toggle by means of a second lock pin 80 which traverses the side walls of the second groove 68 and the lug 76 of the third shank 32. The lug 76 is provided with a flat portion 82 coaxial with the third shank 32 and two recesses 84 spaced from the flat portion 82. As a result, when the second shank 30 and the third shank 32 are arranged coaxially, the flat portion 82 is acted on by the steel ball 74. As soon as the third shank 32 is turned in either direction through an angle of 90 degrees, the recess 84 serves to receive the steel ball 74 so as to maintain securely the third shank 32 in that position.

The sleeve 78 is used to fit over the driver head tips of various shapes and sizes. As an example, a Phillips head tip 86 is shown in all of the accompanying drawings.

As mentioned previously, the coil spring 33 surrounds the first shank 26. One end of the coil spring 33 is received in a circular recess 88 of the stopping sleeve 28 while the other end of the coil spring 33 acts on the circular shoulder 90 formed on the flange 34 of the tubular member 24 in such a manner that the tubular member 24 is urged outwardly.

When the third shank 32 is moved to form an angle of 90 degrees with second shank 30, the tubular member 24 is forced by the coil spring 33 to abut the circular shoulder 44 of the ring sleeve 25 to make the latter have direct contact with the third shank 32.

Accordingly, an L-shaped screwdriver 10 is formed as shown in Figures 2 and 3. An L-shaped screwdriver 10 is capable of rotating a screw and the like with a high turning moment. As soon as the third shank 32 is turned to a position coaxial with the second shank 30, the tubular member 24 can be pushed forward by the coil spring 33 until the position of tubular member 24 has reached its limit. As a result, a straight screwdriver 10 is formed, as shown in Figure 4.

When the screwdriver 10 takes a form of an Lshape, the tubular member 24 can be manually pushed backward to the junction of the second shank 30 and the first shank 26. Then the second shank 30 can be bent to form with the first shank 26 an angle of 90 degrees, and the tubular member 24 is released, to be urged by the coil spring 33 so as to act on the circular shoulder 44 of the ring sleeve 25 to make the latter make contact with the second shank 30. As a result, a Z-shaped screwdriver 10 is formed, as shown in Figure 5, in which the handle 12 is shown rotating rapidly along with the head tip 86 in a direction indicated by the arrow. The rapid rotation of both handle 12 and the head tip 86 is made possible by the tubular member 24 which is in a state of capable of rotating relatively with the handle 12 and the shanks.

Claims

1. A screwdriver comprising an elongate handle having a proximal end and a distal end and having a receiving chamber along the long axis thereof, and a driver device attached to the handle, the driver device comprising: (a) a tubular member having proximal and distal ends and having a through hole along the axis thereof and being lodged in the receiving chamber in such a manner that the tubular member can move in a direction along the long axis of the handle and that the distal end region of the tubular member protrudes beyond the receiving chamber; (b) a first shank, having proximal and distal ends, disposed in the through hole of the tubular member and fixed at its proximal end region with respect to the proximal end region of the handle;; (c) a second shank, having proximal and distal ends, with the proximal end region being pivotally coupled to the distal end region of the first shank; (d) a third shank having proximal and distal ends, with the proximal end region being fastened to the distal end region of the second shank in such a manner that it can be in a first position in which the third shank and second shank are perpendicular to each other or a second position in which the third shank and second shank are aligned with each other, and with the distal end region having a sleeve portion attached thereto; and (e) a biasing means associated with the tubular member in such a manner as to tend to urge the tubular member outwardly from the receiving chamber.

2. A screwdriver according to claim 1, wherein the biasing means comprises a coil spring, having proximal and distal ends, around the first shank, with the proximal end region being lodged in the proximal end region of the receiving chamber and the distal end region being placed at the proximal end region of the tubular member.

3. A screwdriver according to claim 1 or 2, wherein the handle comprises a tubular body which in turn comprises the hollow receiving chamber, a proximal end, a distal end, a substantially hemi-spherical bottom cover fastened to the proximal end region and a circular top cover having a central aperture and attached securely to the distal end region.

4. A screwdriver according to claim 3, wherein the tubular member comprises a flange near its proximal end region and a plurality of ribs located adjacent to the flange, and wherein the circular top cover comprises a plurality of grooves located on its inner wall surface and positioned correspondingly to the ribs for accommodating the ribs.

5. A screwdriver according to claim 3 or 4, wherein the tubular member is fastened to a ring sleeve at the distal end region, the ring sleeve having a ring shoulder disposed thereon.

6. A screwdriver according to any one of claims 3 to 5, when appendant to claim 2, wherein the tubular body of the handle is provided at its proximal end with a through hole and with provision for securement of the substantially hemi-spherical bottom cover, and wherein a stopping sleeve is lodged at the proximal end region of the receiving chamber of the tubular body, the stopping sleeve comprising a circular recess, which in turn is provided with a non-circular recess seat, with a through hole disposed in the recess seat, with the coil spring lodged in the circular recess, with a proximal axial extension of the first shank being lodged in the non-circular recess seat and passing through the through hole to extend beyond the proximal end of the tubular body for attachment to a generally C-shaped clamp piece and to the substantially hemispherical bottom cover, the first shank, at least in its proximal end region, having a body of non-circular cross-section corresponding to the non-circular recess seat of the stopping sleeve.

7. A screwdriver according to any preceding claim, wherein the first shank is provided with a lug located at the distal end region, and wherein the second shank is provided with a first groove located at the proximal end region, the first and second shanks being coupled by means of a pin traversing the side walls of the first groove and the lug.

8. A screwdriver according to any preceding claim, wherein the second shank further comprises a second groove located at the distal end the second groove having a recess hole which is located at the bottom wall thereof and containing therein a coil spring and a steel ball in that order; wherein the third shank comprises a second lug located at the proximal end, the second lug having a flat portion and, spaced therefrom, two recesses to the flat portion, one or other of the recesses serving to receive the steel ball when the third shank is in the first position..

9. A screwdriver substantially as hereinbefore with reference to, and as illustrated in, the accompanying drawings.