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(11) | EP 0 100 105 A2 |
| (12) | EUROPEAN PATENT APPLICATION |
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| (54) | Magazine for fastener driving tool |
| (57) @ A magazine (22) for a fastener driving tool (12) in which the magazine can be readily
spaced from the tool housing (14, 16) in the event a fastener (24) becomes jammed
in the nosepiece (18) of the tool (12) to permit removal of the fastener (24). The
magazine (22) further includes a mechanism (60) whereby when a minimum number of fasteners
(24) is present in the magazine (22), or it is desired to render the tool inoperative,
the fastener follower (26) will engage a lockout mechanism (60) which will prevent
firing of the tool by blocking movement of a work-sensitive probe mechanism (36) which
must be moved in order to fire the tool. |
Technical Field
[0001] This invention relates generally to a novel magazine assembly for a fastener driving tool which includes features that provide for quick and efficient opening of the magazine in the event a fastener becomes deformed and becomes jammed in the nosepiece of the tool and for preventing operation of the tool when desired or when there are but a few fasteners remaining in the magazine.
Background of the Invention
[0002] Fastener driving tools of various kinds are well known to those skilled in the art. These include pneumatic and electrically operated tools as well as other types of tools that are designed for continuous operation and thus include a magazine that holds a plurality of fasteners. The magazine is designed to sequentially introduce a fastener into position to be driven. Various types of magazines have been employed such as those shown in U.S. patents 3,207,405 and 3,815,475 assigned to the assignee of the present invention. These magazines perform satisfactorily but unfortunately there occasionally occurs jamming resulting from a bent nail or some other foreign material which results in the nail becoming stuck in the nosepiece of the tool thus preventing operation thereof. It is, of course, desirable to provide a simple and inexpensive mechanism for permitting disassembly of the magazine to quickly eliminate the fastener that is stuck. Another desirable feature to be included in automatic fastener driving tools is a mechanism whereby the operator can be made aware of the fact that there are relatively few nails left in the magazine and that reloading of the magazine is required. This would obviously improve the efficiency of operation of the tool and eliminate any problems that might arise from firing of the tool when the magazine is empty. In addition it is desired to provide a simple mechanism for eliminating inadvertent operation of the tool. Such a feature by preventing operation of the tool acts to save fuel, reduces the possibility of losing control of one or two fasteners when reloading if the magazine gets this low, and can be used to lock the probe in position when transporting the tool.
Summary of the Invention
[0003] In accordance with the present invention there is provided a novel magazine which includes a portion thereof that forms the guideway for the fastener being driven. This magazine is mounted relative to the nose portion of the main body of the tool and can readily be moved relative thereto so that any fastener jammed therein can be readily withdrawn. In addition, there is provided a mechanism which restricts movement of the work sensitive probe assembly and thus prevents operation of the tool when operation is not desired or when there are but a few fasteners remaining in the magazine. This is accomplished by having the follower that normally acts to bias the nails into position in the nosepiece contact a lock out bracket when desired or automatically when there are but a few nails remaining in the magazine. The lock out bracket is moved into position to halt movement of the work sensitive probe assembly which thus prevents firing of the tool and immediately brings to the attention of the operator that he is about to run out of fasteners and that they should be replenished. When the fasteners are replenished the follower is retracted and the lock out bracket which is normally spring-biased into a disengaged position is moved out of contact with the work sensitive probe to permit normal operation of the tool.
[0004] Numerous other advantages and features of the invention will become readily apparent from the following detailed description of the described embodiment, from the claims and from the accompanying drawings.
Brief Description of the Drawings
[0005]
Figure 1 is a partial cross-sectional side elevational view of a portable tool employing the novel magazine assembly;
Figure 2 is an enlarged detailed view of the magazine showing it spaced from the nosepiece to permit unjamming of the nosepiece;
Figure 3 is a view taken along line 3-3 of Figure 2;
Figure 4 is a view showing the lock out bracket in position to prevent operation of the tool due to there being but a few fasteners remaining in the magazine;
Figure 5A is a view taken along line 5-5 of Figure 2 showing the follower out of engagement with the nail strip; and
Figure 5B shows the follower in engagement with the nail strip.
Detailed Description
[0006] Referring now to Figure 1 there is shown in general outline form a fastener driving tool that is powered by the pressure produced by the combustion of a fuel and air mixture. This type of tool is by way of example only since the novel magazine assembly disclosed herein can be employed with various types of fastener driving tools including those that are pneumatically and electrically operated. Only those general details of the tool that relate to the present invention will be dealt with herein. Further details of the illustrated tool as set forth in an application entitled "Portable Gas Powered Fastener Driving Tool", Serial No. 402,770, filed July 28, 1982 and assigned to the assignee of the present invention.
[0007] The types of tools to which the present applies include those that have a magazine secured thereto which magazine is adapted to receive a plurality of fasteners such as nails that are sequentially biased into position to be driven into a workpiece by a driver secured to a driving piston operated by high pressure air, combustion gases or other energy sources.
[0008] As briefly referred to above there are a number of novel aspects of the unique magazine assembly. These include (1) the mechanism whereby the magazine assembly can be readily spaced from the nose portion of the tool to remove a fastener that may be jammed in the nosepiece and (2) a mechanism for preventing operation of the tool when operation is not desired or when there are no fasteners or a small number of fasteners i.e. 4 or 6 in the magazine. With respect to the first feature i.e., the ready opening of the magazine to eliminate a nail stuck in the nosepiece the fastener driving tool need not include a work sensitive probe assembly whereby the tool will only operate when the nosepiece is placed in contact with the workpiece. However since another important feature of the novel magazine which prevents operation of the tool when there are but a few fasteners remaining in the magazine works in conjunction with a work sensitive probe assembly the two features are illustrated with respect to the same tool. With respect to the work sensitive probe assembly it is important to note that the details of this assembly and its interrelationship with the operation of the tool are not critical. That is to say that the aspect of the magazine preventing operation of the tool when there remain but a few fasteners in the magazine only requires that the work sensitive probe assembly include a member that must move relative to the nosepiece before the trigger can be operated to fire the tool. Thus the novel lockout mechanism can be used with any of a number of other designs of probe assemblies or "bottom trip mechanisms" as they are sometimes referred to.
[0009] Referring now specifically to Figure 1 there is shown a fastener driving tool 12 having a main body portion 14 and a handle portion 16. Located below the main body portion 14 is a nose portion 18 and downwardly disposed from the handle portion 16 is a foot portion 20. The novel magazine assembly 22 is secured at its rear portion to the foot portion 20 and the front end thereof is disposed adjacent the nose portion 18.
[0010] Located within the magazine is a strip of nails 24 which is biased into position in the nosepiece by a follower 26, which follower is biased against the nail strip by a conventional constant force spring assembly 28.
[0011] The tool is operated by actuation of the trigger 30 which effects movement of the driving piston 32 and associated driver blade 34 that extends through the nosepiece 18. The operation of the trigger 30 is controlled by the work sensitive probe assembly 36. In the instant tool the trigger 30 cannot be fired unless the work sensitive probe assembly is moved upwardly relative to the nosepiece 18 to effect release of a trigger interlock assembly 38, the details of which are not important to an understanding of the present invention. However, if further information is desired regarding the interrelationship between the illustrated trigger and work sensitive probe assembly reference is made to the aforementioned application entitled Portable Gas Powered Fastener Driving Tool, Serial No. 402,770.
[0012] As-previously mentioned, the novel lockout feature of the magazine disclosed herein can be used in conjunction with any of various types of work sensitive probe assemblies and associated trigger interlock mechanisms so long as the trigger cannot be operated unless the probe assembly moves relative to the nose assembly a predetermined amount. Similarly, while the trigger mechanism employed herein is to effect operation of a gas fired tool it can also be employed to control a valve mechanism to admit high pressure air to drive the piston or control the operation of an electrically controlled tool. The force used to drive the piston is not critical so long as the trigger controls the application of such force.
[0013] Referring now to Figure 2 there is shown as an enlarged view of the magazine, the main portion of which is supported relative to the nosepiece by a pair of pins 40 extending into openings 42 formed in the fixed nose guide 18 (only one pin and opening are illustrated). The magazine is loaded with fasteners 24 with the follower 26 being located in the retracted position as shown in Figure 5B. The rear end of the magazine is supported relative to the foot portion 20 of the handle 16 of the driver tool by the interengagement of serrated teeth 44, 46 formed on members 45 and 47 secured to the foot portion 20 and magazine 22 respectively (see Figure 3). The serrated teeth 44, 46 are retained in locking engagement by a threaded knob assembly 50 and associated nut 52. The foot portion 20 defines an elongated slot 54 in which the knob assembly 50 is free to slide. When the knob 50 is loosened to permit separation of the toothed members as shown in Figure 3 the magazine 22 can be moved to the right into the position shown in Figure 2.. In this position it can be seen that the magazine and associated pins 40 are moved relative to the nosepiece with the result that a gap 56 is provided between the nose guide portion and the adjacent end of the magazine to permit removal of any fastener that may be jammed therein. Upon removal of the fastener the magazine can be moved to the left and the serrated teeth reengaged by tightening of the threaded knob assembly 50 to lock the magazine in position adjacent the nose guide.
[0014] As shown in Figure 2 there are a substantial number of fasteners in the magazine and the follower assembly 26 is located substantially back from the nose of the tool in the manner shown in Figure 5B. As the fasteners are used, the follower assembly 26 moves forwardly on the rail 58 (see Figure 5) by the action of the constant force spring 28 until a few fasteners remain and the follower ends up in the position shown in Figure 4. It is at this juncture that the follower 26 engages a lock out bracket 60 which acts to "lock out" or prevent the tool from being fired. The bracket 60 is affixed to the magazine 22 by a fastener 63 extending through an elongated slot 68 in the bracket. Bracket 60 is free to move relative to fastener 63 and is normally held in the position shown in Figure 2 by a spring 61 located between an abutment (not shown) on the magazine and a downwardly turned flange 64 on the lock out bracket. When the follower 26 engages the flange 64 of the lock out bracket it is moved against the action of the spring 61 to where the end 65 of the lock out bracket comes into contact with the nosepiece immediately above the location of the generally tubular work sensitive probe member 66. With the bracket in the nosepiece engaging position the probe 66 cannot be moved relative to the nosepiece a sufficient distance to release the trigger lockout mechanism 38 to allow the trigger 30 to be operated to fire the tool. Thus, when the magazine is left with but a few fasteners the lock out bracket prevents the operation of the fastener tool.
[0015] Referring now to Figures 5A and 5B there is illustrated two positions of the follower assembly 26. In Figure 5A the follower has been moved to by-pass the nail strip and thus the constant force spring will move the follower into contact with the lockout bracket to prevent firing of the tool even though there are nails in the magazine. This is done when it is desired to lock the probe in position when the tool is being transported or not in use.
1. A fastener driving tool (12) including a housing (14,16) containing a nose assembly
(18) and a magazine assembly (22) for successively feeding fasteners (24) to be driven
by said tool (12), the improvement characterized in that means (40,42,44,45,46,47,50,52,54)
are provided for securing said magazine assembly (22) relative to said housing (14,16)
to allow movement of said magazine (22) between a fastener (14,16) feeding position
closely adjacent said nose assembly (18), and a release position spaced therefrom
to permit removal of a fastener (24) that may be jammed in the nose assembly (18),
said securing means comprising cooperating aligned guide pins (4) and openings (42)
between the nose assembly (18) and one end of the magazine (22), and interlocking
means (44,45,46,47, 50,52,54) between the housing and other end of the magazine.
2. A fastener driving tool as set forth in claim 1 characterized in that the guide
pins (40)are part of the magazine and the aligned openings (42) are defined by said
nosepiece (18).
3. A fastener driving tool as set forth in claims 1 or 2 characterized in that the
interlocking means between the housing (14,16) and said other end of the magazine
and housing (16) comprises cooperating serrated segments (44,45,46,47) and a knob
assembly (50,52) for retaining the segments (45,47) together in the desired position.
4. A fastener driving tool as set forth in claim 3 characterized in that one of said
housing (16) or magazine (22) defines a slot (54) through which said knob assembly
(50,52) extends whereby the magazine (22) can be affixed in position relative to said
housing (16) by said knob assembly (50,52) when the magazine (22) is located immediately
adjacent said nose assembly (18) or spaced therefrom as desired.
5. A portable fastener driving tool (12) comprising a housing (14) including a nose
assembly (18), a cylinder in said housing (14), a piston (32) in said cylinder, a
driver (34) attached to said piston (32) and extending into said nose assembly (18),
a magazine assembly (22) secured to said housing (14) adjacent said nose assembly
(18) including means (26) for supplying fasteners (24) into position to be driven
by said driver (34), means (30) for operating said tool to move said piston (32) to
drive a fastener (24) into a workpiece, a work sensitive probe assembly (36) slidably
supported relative to said nosepiece (18) for controlling said tool operating means,
the improvement characterized in that it includes means (60,64,65) on said magazine
(22) disposed adjacent said nosepiece (18) and proble assembly (36) responsive to
the means (26) for moving fasteners into position to be driven for limiting movement
of said work sensitive probe assembly (36) to prevent operation of said driving tool
(12) when a small number of fasteners remain in said magazine (22).
6. A portable fastener driving tool as set forth in claim 5 characterized in that
the work sensitive probe assembly (36) includes a generally tubular member (66) disposed
about said nosepiece (18) that is normally spring biased outwardly with respect to
said nosepiece (18) and in which the means for moving the fasteners into position
to be driven includes a spring biased fastener follower (26) and the means limiting
movement of the work sensitive probe assembly (63,68) comprises a lockout bracket
(60) movably secured relative to said magazine and positioned to be engaged by said
follower (26) and moved into blocking engagement with said work.sensitive probe (36)
to prevent operation of said driving tool when a small number of fasteners (24) remain
in said magazine (22).
7. A fastener driving tool as set forth in claim 6 characterized in that the lockout
bracket (60) is connected to said magazine by a fastener (63) extending through an
elongated slot (68) defined by said bracket (60) which permits movement of said bracket
(60) relative to said magazine (22) and the bracket is normally biased out of blocking
engagement with said work sensitive probe (36) by a spring (61) extending between
the magazine and a flange (64) on said bracket (60) which flange is positioned to
be engaged by said follower (26) shortly before the magazine (22) runs out of fasteners
(24).
8. A portable fastener driving tool comprising a housing (14) including a nose assembly
(18), a cylinder in said housing (14), a piston (32) in said cylinder, a driver (34)
attached to said piston (32) and extending into said nose assembly (18), a magazine
assembly (22) secured to said housing (14) adjacent said nose assembly (18) including
spring biased follower means (26) for supplying fasteners (24) into position to be
driven by said driver, means (30) for operating said tool to move said piston (32)
to drive a fastener (24) into a workpiece, a work sensitive probe assembly (36) slidably
supported relative to said nosepiece (18) for controlling said tool operating means,
the improvement characterized in that it includes means (60,64,65) on said magazine
(22) disposed adjacent said nosepiece (18) and probe assembly (36) responsive to the
follower means (26) for limiting movement of said work sensitive probe assembly (36)
to prevent operation of said driving tool (12) during - transport or when the tool
is not in use.