EP3959038B1

EP3959038B1 - Screwdriver bit and kit comprising a tightening tool and such a bit

Info

Publication number: EP3959038B1
Application number: EP20721526.0A
Authority: EP
Inventors: Jonas STURESSON
Original assignee: Atlas Copco Industrial Technique AB
Current assignee: Atlas Copco Industrial Technique AB
Priority date: 2019-04-26
Filing date: 2020-04-23
Publication date: 2023-06-07
Anticipated expiration: 2040-04-23
Also published as: WO2020216821A1; SE543494C2; JP2022530234A; CN113727811A; EP3959038A1; SE1930137A1; CN113727811B

Description

Technical field

The present invention generally relates to bits for power tools for tightening of screws, more particularly to a screwdriver bit for such a tool having a structure for engaging a tip of a tool.

Technical Background

Electrical power tools for tightening are known to be used in various industries. In order to provide an engagement between the tool and the element to be tightened, such as a screw, so called bits (i.e. screwdriver bits) are commonly utilized. For example, exchangeable bits may be used.
US 2008/072719 A1 discloses a screwdriver bit comprising a body having a first end portion comprising a first engaging structure adapted to engage a fastener head, an opposite second end portion, and an intermediate portion connecting said first end portion and said second end portion, wherein said second end portion comprises a second engaging structure adapted to engage a tip of a tool and wherein said second engaging structure is formed by at least one projecting structure extending in an axial direction.
These bits are subject to wear in various degrees, and have to be changed at certain intervals in order to provide a proper engagement to the screw and in order not to damage the screw as may be the case if a too worn bit is used. Since the process may be time consuming and, depending on the application, since such changes may need to be performed frequently - possibly after every tightening for very critical joints, this process may in some industries have a very large impact on the total time of assembly. Given the high requirements on efficiency and time reduction for every station along an assembly line, such delays may be a major issue for overall assembly efficiency. Further, depending on the steps required to perform the change of bit, unnecessary complexity may be introduced in the assembly process.
In order to speed up and facilitate changing of bits, it is known in the field that tool operators for example shake the tool or handle the tool in other more or less suitable ways in order to force the bit into position. However, apart from being less effective in actually achieving the goal of a correctly placed bit in the tool, such handling of the often complex and advanced tools come with a high risk of damaging the tool and/or the bit.
Hence, there exists a need for improvement in the field of screwdriver bits.

Summary of the invention

Accordingly, it would be desirable to provide a bit for a power tool where the changing and proper arrangement of the bit after such a change has been facilitated. In particular, it would be desirable to provide such a bit providing a fast and convenient change and at the same time reducing complexity of the work station. To better address one or more of these concerns a bit and a kit as defined in the independent claims are provided. Preferred embodiments are defined in the dependent claims.
The invention proposes a kit according to claims 1 and 4 and a use of a screwdriver bit according to claim 5.
According to a first aspect a screwdriver bit is provided, the bit comprising a body having a first end portion comprising a first engaging structure adapted to engage a fastener head (such as a screw head), an opposite second end portion, and an intermediate portion connecting the first end portion and the second end portion, wherein the second end portion comprises a second engaging structure adapted to engage a tip of a tool and wherein the second engaging structure is formed by at least one projecting structure extending in an axial direction A-A.
According to the first aspect, the screwdriver bit provides a solution to the concerns described above by means of a design incorporating an engaging structure, or upper surface coupling means, arranged on an end of the bit which in use may be described as a rear or upper end and which is therefore commonly accessible when the bit is arranged in a screwdriver. This since a common design in screwdrivers, such as for example electric of pneumatic power screw drivers, is a design comprising a so called set screw (or stop screw) for holding the bit in place in the tool. In such a tool, a through hole is provided at the front end of the tool into which the bit may be "dropped" or placed, thereafter the set screw is inserted in the hole and engages (for example by means of thread) the wall of the through hole to thereby lock the bit in place as the stop screw engages the threads and the set screw abut the rear end of the screw thereby preventing axial movement of the bit relative the tool. Further, such set screws commonly comprise a structure at the rear (or upper end) adapted to engage a tip of a screwdriver or similar, such that the stop screw may be secured to the tool by means of rotation. The operator performing the change of the bit therefore commonly needs to have a suitable screw driver nearby.
The bit according to the invention cleverly utilizes this already present screwdriver by comprising a structure at it second end which may be adapted to engage this screwdriver. Accordingly, the operator may use the same screwdriver to conveniently put the bit into position by engaging this engaging structure and thereby for example to push the bit into place and/or rotate the bit into a desired rotational position and this operation is then followed by a tightening of the set screw using, again, the same screwdriver.
More particularly, the design of the second engaging structure of the bit may for example be designed to correspond to the design of the engaging structure at the upper, or rear, end of the stop screw such that the operator may even more conveniently utilize the same screw driver for both operations.
Hence, the design of the bit cleverly solves the problem of excessive time spent on changing of bits as well as reduces the complexity of the change operation as such and also of the work station as a whole, utilizing the screwdriver already needed in order to tighten the set screw.
Accordingly, according to one embodiment, the second engaging structure is adapted to engage a tip of a screwdriver.
The referenced tool in which the bit may be arranged is a tightening tool such as a screwdriver, for example a power screwdriver such as a pneumatic an electrical screwdriver, possibly a battery driven tool. More particularly, the screwdriver bit may be suitable for use with a power screwdriver comprising a set screw for holding the bit as described above, where one example include a crowfoot tool, i.e. a tool comprising a crowfoot extension.
The second engaging structure is formed by at least one projecting structure extending in an axial direction, more particularly extending from or with respect to said rear portion. For example, the at least one projecting structure may extend in the axial direction from a substantially planar rear surface of the rear portion. Such a surface may be a surface normal to said axial direction. In general throughout the present specification, if nothing else is indicated, by axial should be understood a direction along the screwdriver bit body, i.e. between the first and second end portion of the screwdriver bit. The skilled person off course realizes that such a structure may equally well be described as a recessed structure, i.e. a recess for engaging a tip of a tool, depending on the reference surface.
According to one embodiment, the at least one projecting structure at least partly encloses a recessed portion adapted to receive a tip of a tool. For example, a recess defined by a surrounding projecting structure may be provided in the upper surface of the bit, forming said engaging structure, whereas a fitting protrusion may be provided by the tool tip such that they may be brought in to an engagement so that a torque may be transmitted. According to one embodiment, the at least one projecting structure forms a hole adapted to receive a tip of a tool. In one embodiment, such a hole may have a hexagonal cross section. In other embodiments, such a hole may have a double hexagonal cross section. Any other shape is however conceivable within the scope of the present invention.
According to one embodiment, the second engaging structure is formed by, i.e. comprises, at least two projections extending in an axial direction and spaced from one another in a circumferential direction. For example, two or more tongues or pins or the like may be arranged in any suitable pattern at the second end portion of the bit to extend in the axial direction. In some embodiments, such a structure may be achieved by means of a slotted structure. For example, the second engaging structure may comprise a hollow axially extending structure, i.e. a protruding structure surrounding a recess, through which a radial slot may be introduced thereby creating two or more section. Such a design may be advantageous both in terms of manufacturability and in that less material may be needed for the bit.
According to one embodiment, the at least two projections form a castellated projecting structure extending in an axial direction, said structure comprising slots spaced from one another in a circumferential direction. By castellated should in the context of the present specification be understood a structure comprising a substantially round, i.e. cylindrical, axially projecting structure, i.e. what may be referred to as a base structure, through which one or more radial slots or notches have been introduced forming the at least two axial projections. Accordingly, castellated in this sense refers to the resemblance with the serrated tops of castle parapets, i.e. the crenellated parapet of a medieval castle. According to one embodiment, the castellated projection structure comprises slots equally spaced from one another in a circumferential direction.
According to one embodiment, the second engaging structure is adapted to engage a tool tip having a hexagonal cross section. For example, the second engaging structure may be a hole having a hexagonal cross section or a slotted, or castellated structure, adapted to engage a hexagonal tip. Such a design is advantageous in that a hexagonal, also known as Allen, is a common screwdriver type readily available to a worker on for example an assembly line. Further, this cross section is also a common choice for the engaging structure on the rear end of the set screw described above and thus also the shape of the screwdriver used to tighten this screw. In one embodiment, the at least one projection has a double hexagonal shape, i.e. a double hexagonal cross section.
According to one embodiment, the second engaging structure is adapted to engage a tip of a tool of a type chosen from a group comprising Torx, Square and Triangle. In other embodiments, the second engaging structure may be adapted to engage a tip of a tool of any other common type such as slot, cross (also known as Philips) or square (also known as Robertsson). In one embodiment, the intermediate portion of the bit comprises a hexagonal cross section.
According to one embodiment, the total length of the screwdriver bit lies in the range 10-50 mm, in some embodiments in the range 15-25 mm. According to one embodiment, the length of the second engaging structure bit lies in the range 2-5 mm.
According to a second aspect, a kit comprising a screwdriver bit according to any of the embodiments described above and a tightening tool comprising a set screw for locking the bit in the tightening tool is provided, the set screw comprising a thread for engaging a corresponding thread in a through hole at a front end of the tightening tool to lock the bit and a rear surface comprising engaging means adapted to engage a tool tip of a first type, wherein the second engaging structure of the screwdriver bit adapted to engage a tip of a tool is adapted to engage a tool tip of the first type. Accordingly, in such a kit, the engaging means of the rear surface of the set screw and the engaging means on the second end portion of the bit may be made to match, i.e. adapted to engage a tool tip of the same size and shape, the advantages of which has been explained above. By rear surface should be understand a surface at an end opposite to the end of the set screw facing, possibly abutting, the screwdriver bit.
According to one embodiment of the second aspect the rear surface of the locking screw comprising engaging means adapted to engage a tool tip of a first type is adapted to engage a screwdriver tip of a first type, and wherein the second engaging structure of the screwdriver bit adapted to engage a tip of a tool is adapted to engage a screwdriver tip of the first type. As explained above, a hex- or Allen-screwdriver is a possible choice of type of screwdriver.
According to a further embodiment of the second aspect, the front part of the tool is a crowfoot extension.
According to a third aspect, a kit comprising a screwdriver bit according to any of the embodiments described above and a crowfoot extension for a power tool comprising a set screw for locking the bit in the crowfoot extension is provided, the set screw comprising a thread for engaging a corresponding thread in a through hole at a front end of the crowfoot to lock the bit and a rear surface comprising engaging means adapted to engage a tool tip of a first type, wherein the second engaging structure of the screwdriver bit adapted to engage a tip of a tool is adapted to engage a tool tip of the first type.
Objectives, advantages and features of the respective kits conceivable within the scope of the second and third aspect are readily understood by the foregoing discussion referring to the first aspect.
Further objectives of, features of and advantages of the present invention will become apparent when studying the following detailed disclosure, the drawings and the appended claims. Those skilled in the art realize that different features of the present invention can be combined to create embodiments within the scope of the claims other than those described in the following.

Brief description of the drawings

The invention will be described in the following illustrative and non-limiting detailed description of exemplary embodiments, with reference to the appended drawing, on which

Figure 1 is a perspective view of an exemplary screwdriver bit according to one embodiment.
Figure 2 is a cross sectional view of an exemplary screwdriver bit according to one embodiment.
Figure 3 is a perspective sectional view of an exemplary screwdriver bit according to one embodiment showed together with a set screw arranged in a front part of an exemplary power tool.

All figures are schematic, not necessarily to scale and generally only show parts which are necessary in order to elucidate the invention, wherein other parts may be omitted or merely suggested.

Detailed description

An exemplary screwdriver bit 1 is shown in figure 1, the bit comprising a body having a first end portion 10 comprising a first engaging structure 11 adapted to engage a fastener head such as a screw head, in the illustrated embodiment having a square cross section, an opposite second end portion 20, and an intermediate portion 30 connecting the first end portion 10 and the second end portion 20. Hence, the first end portion 10 is the portion of the bit facing away from the tool when arranged in the tool (i.e. the distal part), whereas the second portion 20 is the portion of the bit facing away from the tool when arranged in the tool (i.e. the proximal part).
The second end portion 20 comprises a second engaging structure 21 adapted to engage a tip of a tool, in the illustrated embodiment more particularly to engage a tip of a screwdriver. As may be seen from fig. 1, this second engaging structure comprises, or is formed by, three projecting structures 21a-c spaced from one another in a circumferential direction and extending in an axial direction A-A defined between the first and second end portions 10, 20. These projecting structures 21a-c may be described as at least partly enclosing a recessed portion 22 in which the screwdriver tip may be received.
More particularly, the three projections 21a-c in the illustrated embodiment form what may be described as a castellated projecting structure 21a-c extending in the axial direction A-A and comprising slots 23a-c equally spaced from one another in a circumferential direction of the bit 1.
The shape of the projections 21a-c is such that a screw driver tip having a hexagonal cross section, i.e. a hex or Allen key, may be exchanged by the projections. The cross section of the respective projection 21a-c, as may be seen in figure 2, therefore comprises an outer arch shaped portion 24 (i.e. corresponding or following the circular circumference of the second end portion 20 of the bit 1, two inclined portions 25a-b and a straight inner portion 26. Hereby every other edge of a hex shaped screwdriver tip may abut and engage a straight portion 26 (as the screwdriver is used to position the bit properly).
In the illustrated exemplary embodiment, the total length of the screwdriver bit, from the first 10 to the second end portion 20 is approximately 20 mm, whereas the axial length of the projection structure 21a is approximately 2 mm.
In the case of a projecting structure 21a having a continuous non-slotted design, instead a hole adapted to receive a tip of a tool (in this case a hexagonal, or Allen type, screwdriver) could be arranged at the upper, or rear, end of the bit.
In figure 3, the screwdriver bit 1 is shown arranged in a front part 200 of a tightening tool, the tool comprising a set screw 110 (or locking screw) for locking the bit 1 to the tool. In the illustrated embodiment, the bit and hence the set screw are arranged in a so called crow foot 200, i.e. the front part 200 of the tool is a crow foot extension 200.
The crowfoot 200 at its front end 210 comprises a through hole 211 having at thread 211a for engaging a thread 111 on the set screw 110 to lock the set screw 110 and hence the screwdriver bit 1 which in use is positioned below the set screw 110 in the tool. In the illustrated embodiment, the set screw 110 at its rear surface 112 comprises engaging means 112a in the form of a recess, or hole 112a, having a hex-shaped cross section and thus being adapted to engage an Allen, or Hex, screwdriver in order to allow the set screw 110 to be tighten.
The screwdriver bit in fig. 3 comprises the same second engaging structure 21a-c as the embodiments illustrated in figures 1 and 2, i.e. having three projecting structures 21a-c spaced from one another in a circumferential direction and extending in the axial direction, and is hence adapted to engage a hex- or Allen screwdriver tip. More particularly, the engaging structure is adapted to be able to engage a hex- or Allen type screwdriver of the same size as the hex-shaped hole 112a at the upper, or rear, end 112 of the set screw 110.
During operation of the tool, as the operator needs to change the bit, he or she may thus use a hex-screwdriver to unscrew the set screw 110 from the through hole 211 in the crowfoot extension 200, remove the used bit 1 (if necessary by means of engaging the castellated structure 21a-c at the rear end 20 of the bit 1), inserting a new bit 1 in the hole and using the same hex-screwdriver to engage the projecting structures 21a-c to conveniently position the bit 1 in the correct position (including rotation of the bit 1 and axial translation on the bit). Finally the set screw 110 may be tightened, again using the same Hex-screwdriver. Accordingly, the operator may perform the entire operation fast and efficiently using just one tool, this tool being a standard screwdriver, and without the need for any undesirable tough handling of the tool which may cause damage to the bit and/or the tool.
While the invention has been illustrated and described in detail in the drawings and foregoing description, such illustration and description are to be considered illustrative or exemplary and not restrictive; the invention is not limited to the disclosed embodiment. The skilled person understands that many modifications, variations and alterations are conceivable within the scope as defined in the appended claims.
In the claims, the word "comprising" does not exclude other elements or steps and the indefinite article "a" or "an" does not exclude a plurality. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. Any reference signs in the claims should not be construed as limiting the scope of the claims.

Claims

Kit (100) comprising a screwdriver bit (1) comprising a body having
a first end portion (10) comprising a first engaging structure (11) adapted to engage a fastener head,

an opposite second end portion (20), and

an intermediate portion (30) connecting said first end portion and said second end portion,

wherein said second end portion comprises a second engaging structure (21) adapted to engage a tip of a tool and wherein

said second engaging structure is formed by at least one projecting structure (21a; 21b; 21c) extending in an axial direction A-A, and
a tightening tool comprising a set screw (110) for locking said bit in said tightening tool, said set screw comprising a thread (111) for engaging a corresponding thread (211a) in a through hole (211) at a front end (210) of said tightening tool to lock said bit and a rear surface (112) comprising engaging means (112a) adapted to engage a tool tip of a first type,

wherein the second engaging structure (21) of said screwdriver bit (1) adapted to engage a tip of a tool is adapted to engage a tool tip of said first type.
Kit according to claim 1, wherein said rear surface of said set screw comprising engaging means adapted to engage a tool tip of a first type which is adapted to engage a screwdriver tip of a first type, and wherein the second engaging structure of said screwdriver bit adapted to engage a tip of a tool is adapted to engage a screwdriver tip of said first type.
Kit according to claim 1 or 2, wherein said front end (210) of said power tool is a crowfoot extension.
Kit comprising a screwdriver bit comprising a body having
a first end portion (10) comprising a first engaging structure (11) adapted to engage a fastener head,

an opposite second end portion (20), and

an intermediate portion (30) connecting said first end portion and said second end portion,
wherein said second end portion comprises a second engaging structure (21) adapted to engage a tip of a tool and wherein said second engaging structure is formed by at least one projecting structure (21a; 21b; 21c) extending in an axial direction A-A, and
a crowfoot extension for a power tool comprising a set screw for locking the bit in the crowfoot extension, the set screw comprising a thread for engaging a corresponding thread in a through hole at a front end of the crowfoot to lock the bit and a rear surface comprising engaging means adapted to engage a tool tip of a first type, wherein the second engaging structure of the screwdriver bit adapted to engage a tip of a tool is adapted
to engage a tool tip of the first type.
Use of a screwdriver bit in a tightening tool, the screwdriver bit comprising a body having
a first end portion (10) comprising a first engaging structure (11) adapted to engage a fastener head,

an opposite second end portion (20), and

an intermediate portion (30) connecting said first end portion and said second end portion,

wherein said second end portion comprises a second engaging structure (21) adapted to engage a tip of a tool and wherein said second engaging structure is formed by at least one projecting structure (21a; 21b; 21c) extending in an axial direction A-A, the tightening tool comprising a set screw (110) for locking said bit in said tightening tool, said set screw comprising a thread (111) for engaging a corresponding thread (211a) in a through hole (211) at a front end (210) of said tightening tool to lock said bit and a rear surface (112) comprising engaging means (112a) adapted to engage a tool tip of a first type, wherein the second engaging structure (21) of said screwdriver bit (1) adapted to engage a tip of a tool is adapted to engage a tool tip of said first type.
Use according to claim 5, wherein said tool comprises a crowfoot extension.
Kit according to claims 1-4 or use according to claims 5-6, wherein said at least one projecting structure (21a; 21b; 21c) at least partly encloses a recessed portion (22) adapted to receive a tip of a tool.
Kit or use according to claim 7, wherein said at least one projecting structure (21a; 21b; 21c)forms a hole adapted to receive a tip of a tool.
Kit or use according to claim 7 or 8, wherein said second engaging structure comprises at least two projections (21a, 21b) extending in an axial direction and spaced from one another in a circumferential direction.
Kit or use according to claim 9, wherein said at least two projections form a castellated projecting structure extending in an axial direction, said structure comprising slots (23a, 23b) spaced from one another in a circumferential direction.
Kit or use according to claim 10, wherein said castellated projection structure comprises slots equally spaced from one another in a circumferential direction.
Kit or use according to any of the preceding claims, wherein said second engaging structure is adapted to engage a tool tip having a hexagonal cross section.
Kit or use according to any of the preceding claims 1-11, wherein said second engaging structure is adapted to engage a tip of a tool of a type chosen from a group comprising Torx, Square and Triangle.
Kit or use according to according to any of the preceding claims, wherein the total length of the screwdriver bit lies in the range 18-50 mm.
Kit or use according to any of the preceding claims, wherein said second engaging structure is adapted to engage a tip of a screwdriver.