Hand tool

Abstract

 The invention relates to a hand tool (1) comprising a shaft (2) and a tool part (6) lockable in a detachable manner thereto by means of a connection mechanism (4) which comprises a spigot (8) and a socket (10) that are detachably interconnectable, which spigot (8) comprises a flexible element (12) that protrudes outwardly from the spigot surface (8) and which socket (10) comprises a gap (14) to receive the flexible element (12) when the spigot (8) is set inside the socket (8) for interlocking the shaft (2) and the tool part (6). According to the invention, the connection mechanism (4) comprises a sliding piece (16) mounted on top of the socket (10) and movable in the axial direction of the socket (10) for pressing the flexible element (12) out of the gap (14).

Description

BACKGROUND OF THE INVENTION

[0001] The invention relates to a hand tool and, in particular, to a hand tool in accordance with the preamble of claim 1, which hand tool comprises a shaft and a tool part lockable in a detachable manner thereto by means of a connection mechanism which comprises a spigot and a socket that are detachably interconnectable, which spigot comprises a flexible element that protrudes outwardly from the spigot surface and which socket comprises a gap to receive the flexible element when the spigot is inserted inside the socket for interlocking the shaft and the tool part.

[0002] In accordance with prior art, many hand tools, such as garden tools, utilize the same kind of shaft or handle at one end of which a tool part is provided. Thus, it is advantageous that a tool head is provided exchangeable, whereby it is possible to connect two or more different tool heads to the one and the same shaft. Detachable connection of the tool head to the shaft is carried out with a connection mechanism in connection with the prior art. The connection mechanism generally comprises a socket and a spigot, which spigot is provided to be inserted into the socket. Further, in accordance with the prior art, the spigot is provided with or thereon is mounted a connecting part, such as a pin or a strip/clip, that protrudes in a flexible or spring-loaded manner outwardly from the surface of the spigot. The socket, in turn, is provided with a gap such that when connecting a tool head to a shaft, the spigot is placed inside the socket such that the connecting part penetrates into the gap or through the gap provided in the socket locking the tool head with the shaft and preventing the relative movement between the tool head and the shaft. Instead of the gap, on the inner surface of the socket it is also possible to provide a claw or the like, against which the connecting part abuts preventing the relative movement between the tool head and the shaft. In accordance with the prior art, in order to unlock the interlocking of the tool head and the shaft the user must press the flexible or spring-loaded connecting part with his finger downwards through the gap in the socket and simultaneously pull the tool head and the shaft apart in the longitudinal direction of the shaft. A prior art solution of this kind is disclosed in publication GB 2209301 A.

[0003] The above-described arrangement has a drawback that the unlocking of the connection mechanism is difficult in practice, because it requires that the connecting part be pressed and the tool head and the shaft be pulled apart simultaneously. In addition, the connecting part is very rigid, in particular in a new hand tool, and consequently sufficiently hard pressing to push the connecting part out of the socket gap is difficult by finger force. Further, both the socket gap and the connecting part of the spigot are exposed, whereby in connection with the use of the hand tool, dirt, such as sand and soil, will intrude into the connection mechanism between the socket gap and the connecting part, which makes it difficult or impossible to press the connecting part through the gap so as to detach the tool head and the shaft from one another.

BRIEF DESCRIPTION OF THE INVENTION

[0004] The object of the invention is to provide a hand tool such that the above problems may be solved. This is achieved by a hand tool in accordance with the characterizing part of claim 1, which is characterized in that the connection mechanism comprises a sliding piece mounted on a socket and movable in the axial direction of the socket so as to press the flexible element out of a gap.

[0005] Preferred embodiments of the invention are disclosed in the dependent claims.

[0006] The invention is based on the idea of providing a hand tool, which comprises a shaft and a tool head connectable to its end by means of a connection mechanism. The connection mechanism comprises a socket and spigot to be inserted therein. The spigot is provided with a flexible element that protrudes outwardly from the surface of the spigot and that may be pressed downwardly, for instance to be on the level with the spigot surface or below the spigot surface. The socket, in turn, is provided with a gap that is arranged to receive the flexible element of the spigot, as the socket is mounted in place around the spigot. On mounting the socket around the spigot, the socket presses the flexible element downwardly until the flexible element is at the socket gap, whereby the flexible element penetrates, for instance by spring force or bending stress, into the socket gap or at least partly therethrough. In the socket gap the flexible element is supported at least to a gap edge that is transversal to the longitudinal direction of the tool shaft locking the tool head to the shaft. The connection mechanism of the invention may be provided such that the spigot is arranged in the shaft of the hand tool and the socket in the tool head, or alternatively, the spigot is arranged in the tool head and the socket in the shaft.

[0007] In accordance with the present invention, on the socket there is further mounted a sliding piece that is movable in the axial direction of the socket, which is, in general, substantially the same as the longitudinal axis of the shaft of the hand tool. The sliding piece is arranged to be set in two positions. In the first position of the sliding piece the connection mechanism is in a locked state such that the flexible element of the spigot is penetrated in the socket gap preventing the shaft and the tool head from being detached from one another. As the sliding piece is moved from the first position to a second position, the sliding piece presses the flexible element of the spigot downwardly and out of the socket gap such that, as the sliding piece is in the second position, the flexible element is pressed down out of the socket gap. In accordance with the above, the sliding piece is placed on the socket such that it covers both the socket gap and the flexible element of the spigot, when the spigot is inserted in the socket.

[0008] The method and the arrangement of the invention have an advantage that by means of the sliding piece the interlocking of the socket and the spigot may be unlocked utilizing the linear movement of the sliding piece and, in addition, by means of the sliding piece the interlocking of the spigot and the socket may be held in a permanently unlocked or locked state by placing the sliding piece in the first or second position. In that case detachment of the tool head of the hand tool from the shaft may be performed such that, first, the interlocking of the socket and the spigot is unlocked by means of the sliding piece by moving the sliding piece such that it presses the flexile element of the spigot out of the socket gap. Thereafter, while the interlocking of the spigot and the socket is and remains unlocked, the shaft and the tool head may be detached from one another by extracting the spigot from the socket. In other words, the connection mechanism of the present invention makes it possible that the mutual unlocking of the shaft and the tool head and the mutual detachment of the shaft and the tool head may be carried out as separate operations and they need not be performed simultaneously. In addition, the sliding piece placed on the socket covers the socket gap and the flexible element of the spigot thus preventing sand and other dirt from intruding inside the connection mechanism, whereby the reliability of the locking mechanism is improved.

BRIEF DESCRIPTION OF THE DRAWINGS

[0009] In the following, the invention will be described in greater detail in connection with preferred embodiments, with reference to the attached drawings, in which

Figure 1 shows an embodiment of a hand tool in accordance with the present invention, in which a tool head and a shaft are detached from one another;

Figure 2 shows the hand tool of Figure 1 the tool head 6 being connected to the shaft and the connection mechanism being in a locked state;

Figure 3 shows the hand tool of Figure 1 the tool head 6 being connected to the shaft and the connection mechanism being in an unlocked state;

Figure 4 is a cross sectional view of the hand tool of Figure 2 the connection mechanism being in the locked state; and

Figure 5 is a cross-sectional view of the hand tool of Figure 2 the connection mechanism being in the unlocked state.

DETAILED DESCRIPTION OF THE INVENTION

[0010] With reference to Figure 1, it shows a hand tool 1 that comprises a shaft 2 having a first end 3 and a second end 5. The first end 3 of the shaft 2 constitutes a handle, which the user may grip, and the second end 5 of the shaft 2 constitutes a tool end, to which a separate tool head 6 may be connected. In Figures 1 to 5 the tool head 6 is a mop, but the tool head 6 may be, for instance, a brush, a rake, a spade, a hoe or any other tool head that is applicable with the shaft 2. Further, the shaft 2 may be straight as in Figure 1 or it may be designed into a handle in a desired manner.

[0011] In accordance with Figure 1, the hand tool 1 also comprises a connection mechanism 4 for connecting a detachable tool head 6 to the second end 5 of the shaft 2. In accordance with the present invention, the connection mechanism 4 comprises a spigot 8 and a socket 8 provided for receiving the spigot 8. In the embodiment of Figure 1, the spigot 8 is provided in the second end 5 of the shaft 2 and the socket 10, in turn, is provided in the tool head 6. In an alternative embodiment, the socket 10 could be provided in the second end 5 of the shaft 2 and the spigot 8 in the tool head 6. The spigot 8 may be a separate part, which is connected to the shaft 2 or to the tool head 6, or it may be an integral part of the shaft 2, for instance the second end 5 of the shaft 2. Further, the spigot 8 may be solid or tubular, and moreover the cross section of the spigot 8 may be round, oval, rectangular or of any other shape. The socket 10, in turn, may be a separate part, which is connected to the tool head 6 or to the shaft 2, or it may be an integral part of the shaft 2, for instance the second end 5 of the shaft 2.

[0012] In Figure 1 the shaft 2 and the tool head 6 are shown detached from one another such that the spigot 8 and the socket 8 of the connection mechanism are apart from one another. For connecting the tool head 6 to the shaft 2 the spigot 8 is inserted into the socket 10. In other words, the spigot 8 is pushed inside the socket 10 in the longitudinal direction of the shaft 2. The spigot 8 is provided with a flexible element 12, which protrudes outwardly from the surface of the spigot 8 and may be pressed flexibly inwardly to the surface level of the spigot 8 or at least partly inside the spigot 8. The flexible element 12 may be provided to flex as such or, alternatively, it may be preloaded to an outwardly protruding position by means of a separate spring (not shown). In the embodiment of Figure 1, the flexible element 12 protrudes in its normal rest position outwardly from the surface of the spigot 8 and flexes and becomes tensioned as it is pressed downwardly. In other words, as pressure on the flexible element 12 stops, it reassumes the position that protrudes from the spigot 8. In the embodiment of Figure 1, the flexible element 12 is a cliplike or flaplike strip that protrudes at an angle outwardly from the surface of the spigot 8. When the spigot 8 is provided at the second end 5 of the shaft 2, the flexible strip 12 protrudes obliquely outwards from the surface of the spigot 8 towards the first end 3 of the shaft 2, as shown in Figure 1, the strip 12 forming an integral part of the spigot 8 in the edge on the tool head side of the shaft 2. If the spigot 8 is provided in the tool head end 6, the strip 12 is arranged to protrude from the surface of the spigot 8 in the opposite direction, i.e. away from the first end 3 of the shaft 2. In accordance with Figure 1, the strip 12 is an integral part of the spigot 8, but alternatively it may also be a separate part. In an alternative embodiment the flexible element 12 may be, for instance, a peg or a like projection protruding outwardly from the spigot 8, which projection may be flexible in itself or it may be made flexible by means of a spring, for instance, or a spring is arranged to preload the flexible element 12 to a position protruding outwardly from the surface of the spigot 8. The flexible element 12 may also be strip or a flap cut in and bended from the spigot 8.

[0013] The socket 10 is further provided with a gap or hole which receives the flexible element 12 in a position protruding outwardly from the surface of the spigot 8, whereby the flexible element 12 penetrates into or through the gap in the socket 10. In Figure 1 the gap in the socket 10 is under a sliding piece 16 shown therein. The gap in the socket 10 is preferably designed such that it substantially corresponds to the shape of the flexible element 12 or at least the shape of the part of the flexible element 12 that protrudes from the surface of the spigot 8. In the embodiment of Figure 1, the gap in the socket 10 is shaped substantially rectangular, or the gap 14 is a slot extending in the axial direction of the socket 10. When the spigot 8 is inserted into the socket 10 for connecting the shaft 2 to the tool head 6, the socket 10, which is dimensioned to fit relatively tightly around the spigot 8, presses the flexible element 12 downwardly to the level of the surface of the spigot 8 until the flexible element 12 reaches the gap of the socket 10, when the flexible element 12 is released, i.e. it is able to bounce back to the position protruding from the surface of the spigot 8. Then, the flexible element 12 penetrates into the gap of the socket 10, or at least partly through the gap, locking the tool head 6 to the shaft 2.

[0014] The interlocking of the spigot 8 and the socket 10 may be unlocked by pressing the flexible element 12 downwardly or inwardly away from the gap of the socket 10, whereby the shaft 2 and the tool head 6 may be pulled apart again in the longitudinal direction of the shaft 2. In accordance with the present invention, the flexible element 12 is pressed downwardly by means of a sliding piece 16 mounted on the socket 10. The sliding piece 16 is provided movable in the axial direction of the socket 10 such that by means of the movement of the sliding piece 16 in the axial direction of the socket 10 the flexible element 12 may be pressed inwardly and out of the gap of the socket 10. The sliding piece 16 may be, for instance, an outer bushing, a split bushing, an outer collar or a split collar, which is arranged around the socket 10, or alternatively, it may be any piece mounted on the socket 10, which is able to press the flexible element of the spigot 8 downwardly and out of the gap of the socket 10 by means of the movement in the axial direction of the socket.

[0015] Figure 2 shows the solution of Figure 1 the tool head 6 being connected to the shaft and locked by means of the connection mechanism 4. In the locked state of Figure 2 the spigot 8 is inserted into the socket 10 such that the flexible element 12 of the spigot 8 is penetrated in the gap of the socket 10. At the same time the sliding piece 16 is in the first position, in which the sliding piece 16 does not press the flexible element 12 out of the socket gap. In Figure 2, the sliding piece 16 is retracted in the first position close to the tool head 6. In order to unlock the locking between the spigot 8 and the socket 10 the sliding piece 16 is moved in the axial direction of the socket 10 to a second position of Figure 6, where the sliding piece 16 presses the flexible element 12 out of the socket gap. In this second position the sliding piece 16 is in a pulled-up position close to the second end 5 of the shaft 2, as shown in Figure 3. In the state of Figure 3, where the locking between the spigot 8 and the socket 10 is unlocked, the tool head 6 and the shaft 2 may be detached from one another by pulling the shaft 2 and the tool head 6 apart in the longitudinal direction of the shaft 2.

[0016] The locked and unlocked states of the connecting means in Figures 2 and 3 are shown in cross-sectional views in Figures 4 and 5, respectively. In accordance with Figure 4, a gap 14 provided in the socket 10 comprises a first edge 20 and a second edge 22 in the axial direction of the socket 10. The sliding piece 16, in turn, comprises a projection 18 provided on the inner surface thereof and protruding from the inner surface. The sliding piece 16 being mounted in place on the socket 10 the projection 18 is able to move in the gap 14 of the socket between the first edge 20 and the second edge 22 of said gap in the axial direction of the socket 10. Thus, the sliding piece 16 is movable between the first and the second positions, in which first position the projection 18 is against the second edge 22 of the gap without pressing the flexible element 12 and in which second position the projection 18 is against the first edge 20 of the gap 14 pressing the flexible element 12 out of the gap 14. In other words, in the locked state the flexible element 12 is arranged to abut onto the first edge 20 while being in the gap 14.

[0017] When the sliding piece 16 is moved in the second position of Figure 5, the projection 18 of the sliding piece 16 presses the flexible element 12 downwards and out of the gap 14. Thus the projection 18 abuts onto the first edge 20 of the gap 14 and the flexible element 12 is out of the gap 14. In accordance with Figures 4 and 5, the travel of the sliding piece 16 for pressing the flexible element 12 out of the gap 14 is arranged to be at least twice longer than the travel of the flexible element 12 when pressed. In that case the force necessary for pressing the flexible element 12 will be low and the use of the connecting mechanism will be easier.

[0018] In order to set the spigot 8 in a correct position inside the socket 10 the spigot 8 may comprise on its outer surface a guide groove (not shown) and the socket 10 comprises a guide projection (not shown), which is arranged to fit in the guide groove when the spigot 8 is inside the socket 10. Alternatively, the guide groove may be provided in the socket 10 and the guide projection on the spigot 8.

[0019] In the embodiment of Figures 1 to 5 the spigot 8 is provided in the second end of the shaft of the hand tool 1 and the socket 10 is provided in the tool part 6, whereby the first edge 20 of the gap 14 is the edge of the gap 14 on the side of the shaft 2, to which edge the flexible element 12 is supported. Alternatively, the spigot 8 is provided in the tool part 6 and the socket 10 is provided in the second end 5 of the shaft of the tool 1, whereby the first edge 20 of the gap 14 is the edge of the gap 14 on the side of the tool part 6, to which edge the flexible element is supported. The shaft 2 may be tubular, whereby the second end 5 of the shaft constitutes the socket 10.

[0020] In the present invention the connection mechanism is provided to lock automatically when the tool head 6 is connected to the shaft 2. In the embodiment of Figure 1 this is provided by furnishing the spigot 8 with one or more pushers 24, which project outwardly from the surface of the spigot 8, as shown in Figure 1. The pushers 24 are provided in that part of the spigot 8 which is not inserted inside the socket 10. Advantageously, the pushers 24 are provided at a point in the spigot 8 which constitutes the limit between the portion of the spigot 8 inserted into the socket 10 and the portion left outside. The pushers 24 are protuberances, pins or the like projections protruding outwardly from the spigot surface. The protuberances 24 are arranged to push the sliding piece 16 to a locking position while the tool head 6 is connected to the shaft 2. In other words, when on connecting the tool head 6 to the shaft 2 the sliding piece 16 is in the second position, in which the sliding piece 16 would press the flexible element 12, the pushers 24 set against the edge of the sliding piece 16 pushing the sliding piece 16 into the first position, in which it does not press the flexible element 12 downwards, while the spigot 8 is inserted into the socket 10. The locking mechanism then sets automatically into a locked state when the tool head 6 is connected to the shaft 2 irrespective of the position of the sliding piece 16 on the socket when connecting the tool head 6. The pushers 24 are advantageously provided in the spigot 8 on the opposite sides of the flexible element 12. The pushers 24 are dimensioned such that the sliding part 16 is able to slide over them when the sliding part 16 is moved to the second position, in which the projection 18 of the sliding part 16 presses the flexible element 12 downwards out of the gap 14 of the socket 10 so as to unlock the locking between the spigot 8 and the socket 10. When the sliding piece 16 is pulled over the pushers 24 to the second position, the sliding piece 16 flexes slightly thus enabling its movement over the pushers 24. In accordance with the above, when the tool head 6 is connected to the shaft 2, the sliding piece 16 being in the second position of Figure 1, the pushers 24 provided in the spigot 8 push the sliding piece 16 to the first position of Figure 2, in which the connection mechanism is in the locked state. Correspondingly, when the sliding piece 16 is moved from the first position of Figure 2 to the second position of Figure 3, in which the connection mechanism 4 is in the unlocked state, the sliding piece 16 is moved over the pushers 24, the sliding piece flexing at the same time.

[0021] It is obvious to a person skilled in the art that as technology advances, the basic idea of the invention may be implemented in a variety of ways. Thus the invention and its embodiments are not restricted to the above examples, but they may vary within the scope of the claims.

Claims

1. A hand tool (1) comprising a shaft (2) and a tool part (6) lockable in a detachable manner thereto by means of a connection mechanism (4) which comprises a spigot (8) and a socket (10) that are detachably interconnectable, which spigot (8) comprises a flexible element (12) that protrudes outwardly from the spigot surface (8) and which socket (10) comprises a gap (14) to receive the flexible element (12) when the spigot (8) is set inside the socket (10) for interlocking the shaft (2) and the tool part (6), characterized in that the connection mechanism (4) comprises a sliding piece (16) mounted on top of the socket (10), which sliding piece (16) is movable in the axial direction of the socket (10) for pressing the flexible element (12) out of the gap (14).

2. The hand tool (1) of claim 1, characterized in that the flexible element (12) is a strip that protrudes at an angle outwardly from the surface of the spigot (8).

3. The hand tool (1) of claim 2, characterized in that the strip (12) is an integral part of the spigot (8).

4. The hand tool (1) of any one of the preceding claims 1 to 3, characterized in that the flexible element (12) further comprises a spring that is arranged to preload the flexible element (12) to a position protruding outwardly from the surface of the spigot (8).

5. The hand tool (1) of any one of the preceding claims 1 to 4, characterized in that the sliding piece (16) is an outer bushing, a split bushing, an outer collar or a split collar, which is arranged around the socket 10.

6. The hand tool (1) of any one of the preceding claims 1 to 5, characterized in that the sliding piece (16) comprises a projection (18) which is provided on the inner surface thereof and arranged to press the flexible element (12) out of the gap (14) when the sliding piece (16) is moved in the axial direction of the socket (10).

7. The hand tool (1) of any one of the preceding claims 1 to 6, characterized in that the gap (14) is a slot extending in the axial direction of the socket (10).

8. The hand tool (1) of claim 6 or 7, characterized in that the projection (18) of the sliding piece (16) is arranged to move in the gap (14) in the axial direction of the socket (10).

9. The hand tool (1) of any one of the preceding claims 1 to 8, characterized in that the gap (14) comprises a first (20) and a second (22) edges in the axial direction of the socket (10), whereby the flexible element (12) is arranged to abut onto the first edge (20) when the flexible element (12) is in the gap (14).

10. The hand tool (1) of claim 9, characterized in that the sliding piece (16) is movable between the first position and the second position, in which first position the projection (18) is against the second edge (22) of the gap (14) without pressing the flexible element (12) and in which second position the projection (18) is against the first edge (20) of the gap (14) pressing the flexible element (12) out of the gap (14).

11. The hand tool (1) of any one of the preceding claims 1 to 10, characterized in that the travel of the sliding piece (16) for pressing the flexible element (12) out of the gap (14) is at least twice longer than the travel of the flexible element (12) when pressed.

12. The hand tool (1) of any one of the preceding claims 1 to 11, characterized in that the spigot (8) comprises on its outer surface a guide groove and the socket (10) comprises a guide projection that is arranged to fit in the guide groove when the spigot (8) is inserted in the socket (10) for setting the spigot (8) and the socket (10) in a correct mutual position.

13. The hand tool (1) of any one of the preceding claims 1 to 12, characterized in that the spigot (8) is provided in one end of the shaft of the hand tool (1) and the socket (10) is provided in the tool head (6).

14. The hand tool (1) of claim 13, characterized in that the first edge (20) of the gap (14) is the edge of the gap (14) on the side of the shaft (2).

15. The hand tool (1) of any one of the preceding claims 1 to 12, characterized in that the spigot (8) is provided in the tool part (6) and the socket (10) is provided in one end of the shaft of the hand tool (1).

16. The hand tool of claim 15, characterized in that the first edge (20) of the gap (14) is the edge of the gap (14) on the side of the tool part (6).

17. The hand tool (1) of claim 15 or 16, characterized in that the shaft (2) of the hand tool (1) is tubular, whereby the second end of the shaft (2) constitutes a socket (10).

18. The hand tool (1) of any one of the preceding claims 1 to 17, characterized in that the spigot (8) is provided with pushers (24) which protrude outwardly from the spigot (8) for pushing the sliding piece (16) to the first position, in which the connection mechanism (4) is in a locked state.

Drawing