US3734379A

US3734379A - Air biased magazine lock and guideway closure for fastener driving tools

Info

Publication number: US3734379A
Application number: US00145755A
Authority: US
Inventors: R Powers
Original assignee: POWERS WIRE PRODUCTS CO Inc
Current assignee: POWERS WIRE PRODUCTS CO Inc
Priority date: 1971-05-21
Filing date: 1971-05-21
Publication date: 1973-05-22
Anticipated expiration: 1990-05-22

Abstract

An air lock and positioning device for the magazine slide and guideway closure of a fastener driving tool, the advantageous features thereof being a substantial reduction in size accompanied by improved locking action and increased safety, whereby readjustment of the magazine slide and guideway closure is continuously affected during operation so as to assure tightness and consequent accurate guideway dimensions, and all of which is accomplished with few and easily formed parts.

Description

United States Patent 1191 Powers 1 1 May 22, 1973 [54] AIR BIASED MAGAZINE LOCK AND 3,610,505 10 1971 Males ..227 123 GUIDEWAY CLOSURE FOR FASTENER 3 22% DRIVING TOOLS 314911931 1/1970 Sales ..227 127 [7 5] Inventor: Richard E. Powers, San Marino,

Calif.

[73] Assignee: Powers Wire Products Co., Inc., El

Monte, Calif.

[22] Filed: May 21,1971

[21] Appl. No.: 145,755

[52] U.S. Cl. ..227/127 [5 1] Int. Cl. ..B27f 7/08 [58] Field of Search.....' ..227/l20,. 123, 127

[56] References Cited UNITED STATES PATENTS 3,140,492 7/1964 Bade ..227/l23 Primary ExaminerGranville Y. Custer, Jr. Attorney-William H. Maxwell [57] ABSTRACT An air lock and positioning device for the magazine slide and guideway closure of a fastener driving tool, the advantageous features thereof being a substantial reduction in size accompanied by improved locking action and increased safety, whereby readjustment of the magazine slide and guideway closure is continuously affected during operation so as to assure tightness and consequent accurate guideway dimensions, and all of which is accomplished with few and easily formed parts.

14 Claims, 13 Drawing Figures Patented May 22, 1933 3,734,379

4 Sheets-Sheet :1

Fla. [2. 26

AIR BIASED MAGAZINE LOCK AND GUIDEWAY CLOSURE FOR FASTENER DRIVING TOOLS BACKGROUND The present invention is concerned with air operated tools for driving fasteners such as staples and nails or the like, wherein air stored under pressure is released in a cylinder and piston motor to operate a driver blade into driving engagement with fasteners sequentially supplied from a magazine. These tools operate explosively so as to strike the fasteners and to hammer them into work with a single blow, removing said fasteners one at a time from a magazinesupply thereof. It is customary for such a magazine to handle a stack of fasteners, usually in stick form wherein a multiplicity of fasteners are severably held together in straight columnar formation, and for such a tool to be characterized by a head with a guideway therethrough adapted to receive individual fasteners from the magazine and to guide them into the work. In dealing with tools and the driving of fasteners of the type under consideration, and because of obstructions in the work or other discrepancies, there are malformations of the fasteners and the jamming thereof in the transmission of the fastener from said magazine and into said work; and for these reasons it is highly advantageous to carry the guideway closure on the magazine slide for retractibility from the head upon withdrawal of said slide. This cooperative relationship opens up the entire workings of the tool and enables the guideway and magazine to be cleared with facility; however problems arise in locking of the guideway closure in tight engagement with the head to thereby complete an accurately cross sectioned guideway. Heretofore these slides have been mechanically locked with various types of spring latches incorporated in the rear portion of the magazine and usually an extended portion making the tool unnecessarily cumbersome. Also, the tightness of the guideway closure has been dependent upon the tolerances and wear in the latch mechanisms, and always prone to accidental release. It is tools of the type thus far referred to which are improved by utilizing the present invention therein.

FIELD OF INVENTION This invention relates to an air lock for the slide of a magazine in a pneumatic tool for driving fasteners that issue out of said magazine and into a guideway completed by a closure element carried by said slide and positioned by the instant air lock, it being a general object of this invention to provide a most effective lock involving the fewest simply formed parts and all of which is incorporated in existing and/or required body structure without encumbering the tool. And as compared with like prior art tools, the tool hereinafter dis closed is of reduced size, is less cumbersome and is safer to use as a result of incorporating the present invention therein, and furthermore is self-adjusting so as to compensate for manufacturing tolerances and wear.

An object of this invention is to reduce the size of the magazine in tools of the type under consideration, specifically by shortening the same through the elimination of the usual space consuming mechanical latches and replacing the same with a compact air pressure biased latch comprising a single moving part. The pneumatic latch hereinafter disclosed is initially biased by a light spring and is forcefully biased into operating position by the working air pressure applied to the tool, thereby discouraging anything except deliberate manual disengagement.

Another object of this invention is to utilize the consistent bias of air pressure supplied to tools of the type under consideration and applied to a self-locking wedge means disposed at a releasable angle and which advances and firmly positions the guideway closure of the tool, holding it fixedly positioned without play.

It is still another object of this invention to provide an improved drive head and magazine mount onto the light weight frame of a fastener driving tool of the type under consideration. With the present invention, the frame is of light-soft metal whereas the magazine is of a heavier-durable metal and the drive head of heavierhard metal; the said frame being provided with mounting lugs clamped between the magazine and head by means of fasteners engaged and threaded with the more durable parts, and the head positioned by means of an extension thereof projecting into a complementary window in the cylinder head of the frame.

DRAWINGS The various objects and features of this invention will be fully understood from the following detailed description of the typical preferred form and application thereof, throughout which description referenceis made to the accompanying drawings, in which:

FIG. 1 is a longitudinal cross sectional view taken through an air operated fastener driving tool, illustrating the air biased magazine lock and guideway closure therefor. FIG. 2 is a fragmentary view of a portion of the structure shown in FIG. 1, illustrating opening of the guideway closure; and FIG. 3 is a fragmentary view illustrating the magazine lock operated so as to permit the movement of parts shown in FIG. 2. FIG. 4 is an enlarged detailed sectional view taken as indicated by line 44 on FIG. 1. FIG. 5 is an enlarged fragmentary view of the magazine lock elements, positioned as shown in FIG. 1, and illustrating the directions of force and adjustment. FIG. 6 is an enlarged sectional view showing the air release of the tool; while FIG. 7 is an enlarged detailed view showing the manually operable button that controls the release. FIG. 8 is an enlarged detailed sectional view taken as indicated by line 88 on FIG. 1. FIG. 9 is a rear quarter perspective view illustrating a unique facer that is inserted into the head construction. FIG. 11 is a sectional view taken as indicated by line l1l1 on FIG. 8.; FIG. 10 is a perspective view illustrating the frame of the head construction which receives the elements illustrated in FIGS. 8 and 9. FIG. 12 is a rear quarter perspective view illustrating the head per se which cooperatively receives the facer shown in FIG. 9. And, FIG. 13 is an enlarged detailed sectional view taken as indicated by line 13-13 on FIG. 1.

v PREFERRED EMBODIMENT A percussively operable cylinder and piston motor and air return means therefor may be used in connection with the air biased magazine lock and guideway closure hereinafter described and, therefore, in the drawings I have illustrated this type of tool. It is to be understood, however, that the present invention is not limited to this particular tool and may be employed to advantage with any fluid pressure actuated tool having a magazine supply of elements to be processed and particularly with those tools wherein the guideway is covered by a removable closure.

The tool, as illustrated in the drawings, is adapted to be handled manually and involves, generally, a frame A having a body portion and a handle or grip portion 11, a head B carried by the frame A and adapted to direct fasteners into a piece of work, a cylinder C adapted to be fixed in the frame A and cooperating therewith to establish an air return means adapted to be charged with fluid under pressure at the end of the work stroke, a piston D adapted to reciprocably operate in the cylinder C and coupled to a driver blade E, there being a snubber F adapted to arrest the piston D and driver blade E and to seal with the piston D at the end of the work stroke, an air release means G adapted to cooperate with the cylinder C and control operation of the piston D, a magazine H for handling a supply of fasteners such as staples to be received by and delivered through the head, and in accordance with the invention an air biased magazine safety lock and guideway closure adjuster means X having a readjustable locking action during operation of the tool.

The frame A carries the various elements of the tool, and is shown in the configuration of a light tacker adapted to be conveniently handled. The frame A involves, generally, the body portion 10 and the handle or grip portion 11, the body portion 10 being a simple elongate part having a cylinder chamber 12 extending longitudinally thereof and having a window 14 through the cylinder head 15 thereof at the lower end of the cylinder chamber 12 for receiving and positioning the head B. The window is preferably polygonal and is shown to be rectangular in cross section, substantially greater than the guideway cross section, having opposed pairs of

parallel walls

16 and 17 normal to the top and bottom 18 of the head 15. In practice, the frame A is made of a light weight softer metal while the head B is made of a heavy and durable heat treated metal; in which case the head B is provided with an extension that projects into the window 14 to be located thereby in order to position the guideway concentric with the drive axis of the tool. Accordingly, the window 14 opens transversely of the head 15, with side walls 16, and with front and rear walls 17; the latter rear wall 17 being coplanar with the front faces 20 of spaced and depending mounting lugs 19 adapted to cooperatively mount both the head B and magazine A as hereinafter described. A facer 21 of durable metal (such as that of the head) covers the wall 17 and faces 20, the portion thereof covering the wall 17 establishing a wall of the guideway, and the portions thereof covering the faces 20 engageably receiving the rear face of the head to position the same. The handle or grip portion 11 is provided to give the person handling the tool a convenient means to hold the tool and is a simple grip of chambered construction that projects at a right angle from the body 10. In practice, the grip 11 is hollow and forms an air pressure accumulator as clearly shown in FIG. 1 of the drawings, and projects laterally from the upper portion of the body 10 a full hands width and more. And, in accordance with the present invention, a strut 22 depends from the outer butt end of the grip portion 11 and which is characterized by a bottom 18' coplanar with the bottom 18 of the cylinder head 15.

In structures of the type under consideration, it is common practice to provide a fluid and lubricant mist pressure supply connection 23 at the grip Ill, such as a pneumatic hose or the like, and also to include a control means I at the grip 11. It is to be understood that such a fluid pressure supply is provided and connected with the grip 11 so as to charge the chamber therein.

The head B is in effect, an extension of the body 10 of the frame A and is provided to receive and guide fasteners such as staples to the work being acted upon by the tool. The head B is carried by the body in the window 14 and is provided with a longitudinal guideway 27 that extends through and below the cylinder head 15. The head B has a seat 24 engaged upon the bottom 18 and it has a front end face 25 engageable with the work, and in accordance with the present invention it has a rectangular extension 26 that projects upwardly from seat 24 and occupies the window 14. In the particular form of the invention shown, the guideway 27 is adapted to handle fasteners or staples S that are U- shaped and formed of wire, or the like, having a pair of sharpened ends (see FIGS. 1 and 2). The staples referred to are substantially elongated with straight parallel shanks joined by a transverse interconnecting back. It will be apparent how the guideway 27 can be proportioned so that it will readily pass the staples with sliding clearance and will act upon the staples to guide them and the driver blade E. A feature of the cooperative magazine and head construction is the simplified rearwardly open channel-shape of the guideway 27 in the head B extending between the top plane of cylinder head 15 and the front end face 25 of the head. As above described, the facer 21 engageably receives the rear face 28 of the head B and completes the rectangular cross section of the guideway 27 with durable hard metal, but only in the area of the head 15. The extension 26 has side walls 16' and a front wall 17 complementary to and having sliding engagement with the

walls

16 and 17 above described; thereby positioning the head B in working position in the frame A.

A cylinder C is a sleeve structure that is inserted into the cylinder chamber 12 to reciprocably receive the piston D and in order to establish a surrounding reservoir 30 adapted to be periodically charged with fluid under pressure. In practice, the fluid reservoir 30 is an annulus established between the straight tubular cylinder wall 31 and wall 32 that forms the cylinder chamber 12. Thus, the fluid reservoir 30 occupies the circumferential area of the cylinder chamber 12 that surrounds the cylinder wall 31. In carrying out the invention, the cylinder C is a simple insert that is pressed into working position with its lowermost end seated in a recess 33 at the bottom of the cylinder chamber 12. A radial flange 34 at the uppermost end of the cylinder slideably engages within the wall 32, and there being a seal at said fit, as shown. The cylinder C with its uppermost flange 34 is characterized by an upwardly faced seat 37 that is cooperatively exposed to the release means G. In the form illustrated, the seat 37 is a flat faced seat in a plane normal to the axis of the cylinder and adapted to be engaged by a flat faced and axially reciprocable valve element 50. In accordance with the invention, the cylinder C is provided with one or more openings 38 at or near the lower end of the cylinder wall 31 and/or reservoir 30, said openings remaining in communication with the interior of the cylinder C at all times, it being sufficient that the piston D does not pass or cross the opening or openings 38.

The piston D operates to reciprocate in the cylinder C and has driving engagement with the driver blade E to move the driver blade forwardly or downwardly. The cylinder chamber 12 is supplied with fluid under pressure by a valve means I so as to effect the piston movement as hereinafter described. The piston body 40 is sealed with the cylinder wall 31 by means of an O-ring 41 engaged therein to have substantial frictional restraint against movement when at rest. However, when said restraint is overcome the piston D is free to move in the cylinder C. The piston D is characterized by a depending body portion 42 of reduced diameter for handling of fluid below the body 40 and for effecting the air return function. The depending body portion 42 is provided with a downwardly disposed face 43 in a plane normal to the piston axis and engageable with the snubber F, and it is this body portion and face 43 which pass the cylinder openings 38. Charging of the reservoir 30 is effected by the provision of a check valve between the cylinder chamber above and below piston D, and as shown involves a circumferential valve seat 46 in the piston portion 42 and a valve element seated therein in the form of an elastic O-ring 47, there being ports 48 extending from the seat to the top of the piston D. It will be apparent that the valve (46-47) permits charging of the reservoir 30 with fluid under pressure.

The driver blade E is essentially a slender elongate part rectangular in cross sectional configuration and terminates at its forward end in a flat fastener or staple driving face 45. The blade E has a lower staple driving portion at the forward end thereof which occupies the guideway 27 of the head B and an upper driven portion 46 at the rear end thereof which couples to the piston D. As shown, the piston D is slotted and there is a pin 44 that positively connects the parts for coupled engagement. In practice, the fit of the driver blade in the guideway 27 is not air tight or leak-proof, but it does afford substantial resistance to fluid flow and thereby restricts volume of leakage, a controlled leakage, especially when related to the short length of time to which said fit of parts is subjected to the return air pressure.

The snubber F is provided for its expected function of stopping the piston D and attached driver blade E, and additionally is provided to seal the reservoir 30 during the short period of time when the piston D and driver blade E are at the lower end of the work stroke. Accordingly, the snubber F is a circular part of substantial depth that surrounds the driver blade E with clearance and that engages and seals with the wall 31 of the cylinder, and which is made of the usual rubber or like elastomeric material and is formed to provide a seat 58 upon which the piston body portion 42 is adapted to have flat sealed engagement. It is at this period and point of engagement that the body 40 is held above the opening or openings 38 for the access of fluid pressure to the underside thereof.

The air release means G that may be employed is disclosed in US. Pat. No. 3,026,849entitled FLUID OP- ERATED VALVE FOR RELEASE OF FLUID UNDER PRESSURE, issued Mar. 27, 1962, and is adapted to cooperate with and control operation of the piston D. The means G is provided to release the piston D from the upper end of the cylinder C and is move and accelerate the piston D when sufficient fluid pressure has been established to effect the desired percussive work stroke. The release means G may involve various and suitable mechanisms to carry out the function referred to without affecting the present invention. For example, the release means F may involve means adapted to shift a valve element 50 between two positions, one where the supply of air is shut off to the cylinder C and air exhausted therefrom, and the other where the supply of air is admitted to the cylinder C and the exhaust is closed. The valve seat 37 at the top end of the cylinder C is exposed to and opens into said chambered grip portion 1 1, to be opened and closed by the valve element 50 of means G. The upper end of the cylinder C is closed by a cap 52, the release means G being carried by and operable through said cap, as clearly shown in FIG. 6.

The valve means J is a fluid pressure exhausting means that retains or exhausts operating fluid in or from the release means G and is preferably formed in and carried by the frame A of the tool and, as shown, there is a three-way valve with a port 53 opening into the pressure chamber, a port 54 open to atmosphere, and a port 55 opening beneath a piston that lifts the valve elements 50 of means G. A manually operable trigger 57 operates a valve 56 to open port 53 to port 55, whereby the valve element 50 of means G is lifted. The said valve element of means J is normally closed, being vented to atmosphere through port 54.

The magazine H which is provided for handling a supply of fasteners to be received and delivered individually through the head B involves a housing 60 supported by the frame A and a slide 70 removable from and shiftably carried by said housing. The housing 60 is an elongated inverted channel that is formed so as to embrace the exterior configuration of the staple S and according to the present invention it has a top 61 that engages flat against the coplanar bottoms 18 and 18'; and it has sides 62 that fit through the mounting lugs 19 to be embraced therebetween. The front of the housing is secured to the lugs 19 by means of ears 63 normal to the sides 62, there being fasteners 64 bearing upon the head B and extending therethrough and through the lugs 19 and threadedly engaged into the said ears. The forward end of the housing is normal and in the plane of the rear guideway interior wall, leaving the guideway 27 open and clear for the reception of individual fasteners S and for severance thereof from a stack of said fasteners progressively advanced into the guideway to be acted upon by the driver blade D. The rear end of the housing 60 is secured to the strut 22 by means of a screw fastener 65 threadedly engaged into the strut, preferably through a tab at the top 61 and threaded into the back of the strut; and in which case the housing extends slightly rearward of the strut as shown. In order to carry the slide 70, the lower margins of the sides 62 are provided with outwardly turned flanges 66 forming tracks, and there are outwardly turned stops 67 at the rear of the housing, projecting from the sides, to engage a removable abuttment on the slide 70.

The slide 70 that is removable from and shiftably carried by the housing 60 is an elongated carriage for the stick of fasteners S that is to be fed thereby into the guideway 27. The slide 70 comprises a cover plate 71 that is coextensive in length with the housing 60 so as to completely close the open channel of said housing, and it carries a closure 72 at its front end to completely enclose the guideway 27 to the front end face 25 of the head B. Thus, the slide 70 includes the plate 71, the closure 72 and a staple rail 73 upon which the stick of fasteners S rides to be pressed forwardly by a follower 74 biased by a spring 75. The closure plate 71 has opposed inwardly open channels that slideably engage over the outwardly turned flanges 66 of the housing 60, the plate being disengageable from said flanges by withdrawing the slide 70 rearwardly. The head closure 72 and rail 73 terminate in a normal plane at the front end of the slide 70, the closure 72 having a flat face 76 engaged with the flat rear face 28 of the head B to complete the rectangular cross section of the guideway 27 in the area of the head extending below the cover plate 71 of the magazine. The staple rail 73 is comprised of a pair of upstanding parallel walls 77 terminating short of the strut 22 and extending to the flat front face 76. Said walls 77 are spaced inward from the housing top 61 and sides 62, thereby forming an inverted U-shaped passageway for the stick of fasteners S. The follower 74 is complementary in cross section to the configuration of the staples S and has a normal forward end to engage and move the stick of staples forwardly, being biased by the tension spring 75 anchored at and within the rear portion of the rail and trained over a sheave 75' next adjacent to the front face 76 and attached to the follower. It will be apparent how the slide 70 is 'retractible so as to be reloaded with sticks of staples S and so as to completely expose the channel of the guideway 27.

In accordance with this invention, l have provided the air biased magazine safety lock and guideway closure adjuster means X that readjusts during operation of the tool while providing safety for the user. Referring back to the frame A and chambered grip portion 11, it is significant that operating air under pressure is accumulated therein and available over the strut 22 by providing a passage 80 through said strut and opening into the chambered grip portion. The safety lock and closure X involves, generally, a cylinder 81 and piston 82, a guideway 83 and crosshead 84, a return spring 85, and a lock bolt 86 and finger grip 87 manipulatable to retract the piston 82, crosshead 84 and lock bolt 86. A feature is the angular disposition of the operational axis of the piston 82, crosshead 84 and especially the lock bolt 86 which cooperatively engages with a rearwardly disposed lock face 88 at the rear of the slide 70. In practice, the said operational axis is tipped downwardly and rearwardly at while the face 88 is tipped likewise at there being a release angle of 10 incorporated in the lock bolt as will be described. The lock face 88 is provided in a part at the rear end of rail 73 which is solid between the walls 77 thereof and with an inclined top 78 to depress the lock bolt 86 before it is projected against lock face 88.

Referring now to the cylinder 81 and piston 82; the cylinder 81 is of moderate diameter as shown and is bored into the grip portion 11 from the bottom 18' of the strut 22 with the passage 80 opening into the same. The piston 82 reciprocates in the said cylinder and has and 0 ring seal 90 to retain the air pressure.

Referring now to the guideway 83 and cross-head 84; the guideway 83 is counterbored through the strut 22 from the bottom 18' thereof, with a shoulder 91 between the same and the bore of cylinder 81. The crosshead 84 is a cylindrical enlargement at the lower end of piston 82 and slideably moves in the guideway 83 to be steadied thereby, and is correspondingly of greater diameter than the piston.

The return spring 85 is a light compression spring that surrounds the piston 81 and presses between the said crosshead 84 and shoulder 91, thereby to urge the piston and crosshead downwardly.

Referring now to the lock bolt 86 and finger grip 87; the lock bolt 86 is an element carried by the piston and crosshead to retractibly project beyond the bottom 18 and through an oversized opening in the cover plate 71 to lockably engage with the lock face 88 on the slide 70. In accordance with the invention, the end portion of the lock bolt is chamfered or tapered at an angle of 10 relative to the operational axis. Consequently, the tapered end portion 92 of the lock bolt has line contact with the lock face 88 being retractile therefrom at an inclined angle substantially less than a normal angle. The conical shape of the end portion 92 and its mode of contact provides for facility in release while the incline of the operational axis provides for increased wedged engagement and ready adjustments. The end result in infinitesimal adjustments as circumstances require while retaining the ability to manually retract the lock bolt 86 at any time. The finger grip or grips 87 are provided as a convenience to retract the lock bolt 86 and preferably a pair of grips carried by the crosshead and exposed at opposite sides of the strut 22. As shown, a bar 94 passes through the crosshead and is guided in a pair of slots 95 at opposite sides of the strut, and to which the finger grips are fastened. The grips 87 are flared outwardly for convenient gripping between a persons fingers when retracting the lock bolt 86.

A removable abutment 100 of plastic or any suitable pliable material adapted to be bent and/or deformed, embraces the opposite margins of the slide 70, underlying the same, and projecting above the cover plate at opposite sides thereof to engage the stops 67. The underlying portion of the abutment 100 has a button 101 engaged in a complementary opening in the cover plate 71 to locate the same at the forward end of the slide 70.

From the foregoing it will be seen that l have provided a unique mounting for the head B and which accurately maintains the normality of the rear face 28 of the head, as is required in order to cooperate with the flat face 76 of the head closure 72 adjusted thereto by means of the magazine safety lock and guideway closure X. With a stick of fasteners S installed on the staple rail 73, the slide is moved forwardly into operating position accompanied by withdrawal of the lock bolt 86 to allow passage of the staples and to ride over the inclined top 78 and followed by its projection behind and into line contact with the lock face 88. It is significant that the crosshead 84 does not bottom against the cover plate 71 through which the lock bolt 86 projects, and to the end that the spring and the air pressured piston 82 forcibly readjust the said line contact. A light pressure is applied to the means X by the spring 85 for loading the tool before use, while a heavy pressure is applied to the means X by the air pressure bias. Consequently, the user of the tool must employ considerable force in order to release the lock bolt 86 when air pressure is connected to the tool, a reminder that the tool is active. However, as a facility in reloading or in clearing a jamb, it is a simple matter to disconnect the air pressure supply hose, thereby assuring safety and with no danger of activating the driver blade D.

Having described only a typical preferred form and application of my invention, 1 do not wish to be limited or restricted to the specific details herein set forth, but wish to reserve to myself any modifications or variations that may appear to those skilled in the art.

I claim:

1. A head construction and guideway closure for a fastener driving too] wherein a driver blade operates to project individual fasteners from a guideway aligned with a magazine disposed normal thereto and feeding individual fasteners into the upper portion of said guideway and wherein the lower portion of said guideway beneath said magazine is a rearwardly open channel closed by a closure positioned thereto by a slide on the magazine, and including: a tool frame having a flat bottom and having spaced depending mounting lugs with coplanar front faces normal to said bottom and having a window through the said frame and extending between said mounting lugs next adjacent to said coplanar faces thereof; a facer seated in said window and having a front wall parallel with said coplanar faces of the mounting lugs; a fastener receiving head carried by said frame and comprising, a body having a top seat engaged with said bottom and a rear face engaged with said coplanar front faces offhe mounting lugs, a channel-shaped fastener guideway disposed normal to the said bottom and between said mounting lugs, and an extension projecting upwardly from the top seat of the body and engaged with said parallel front wall of the facer in said window of the frame; fastener means securing the head to said mounting lugs; a magazine slide movable in a direction normal to the rear face of the head and having a guideway closure with a front face parallel to said rear face of the head; and means releasably forcing the said magazine slide and closure positioned thereby into flat interface engagement with the said rear face of the head and closing the back of the channel-shaped fastener guideway.

2. The head construction and guideway closure for a fastener driving tool as set forth in claim 1, wherein the said facer overlies the said coplanar faces of the mounting lugs and presents a coplanar front wall continuing from the first mentioned front wall of the facer and overlying the said coplanar faces of the mounting lugs, and wherein the rear face of said head body engages said continuing coplanar front wall of said facer.

3. The head construction and guideway closure for a fastener driving tool as set forth in claim 1, wherein the said facer overlies the said coplanar faces of the mounting lugs and presents a coplanar front wall continuing from the first mentioned front wall of the facer and overlying the said coplanar faces of the mounting lugs, wherein the rear face of said head body engages said continuing coplanar front wall of said facer, wherein the magazine of the tool engages with said bottom of the frame and enters between the said mounting lugs and overlying facer and has a pair of mounting ears projecting laterally therefrom, and wherein the fastener receiving head and the said facer pass mounting fasteners therethrough aligned with and extending through the mounting lugs respectively and through the mounting ears of the magazine, thereby clamping the head and facer and magazine onto said lugs and in working position on the frame.

4. A magazine lock in a fluid powered fastener driving tool wherein there is a head and a driver blade that operates through the head, a magazine disposed normal to the head and feeding individual fasteners into said guideway, said tool having a frame and a fluid pressure supply thereto and means controllably operated therewith to project fasteners, said magazine having a housing supported in the frame and having a retractile slide movable toward the head to close the housing, said lock comprising, a cylinder bored in the frame on an axis projecting laterally from the movement plane of the slide, there being open fluid communication between the end of the cylinder remote from the slide and said fluid pressure supply, a piston in the cylinder and biased by the presence of fluid under pressure to move toward the slide, and a lock bolt retractibly shifted by the piston to engage behind a lock face on the slide to hold the slide toward the head.

5. The magazine lock for a fluid powered fastener driving tool as set forth in claim 4, wherein the end portion of the lock bolt is tapered, and wherein the lock face on the slide is slanted at a corresponding angle to have line contact with said end portion of the lock bolt thereby wedging the slide forwardly.

6. The magazine lock for a fluid powered fastener driving tool as set forth in claim 4, wherein the laterally projecting axis of the cylinder and piston and of the lock bolt shifted thereby is slanted to extend downwardly and rearwardly toward the slide thereby facilitating release of said lock bolt.

7. The magazine lock for a fluid powered fastener driving tool as set forth in claim 4, wherein the end portion of the lock bolt is tapered and the laterally projecting axis of the cylinder and piston and of the lock bolt shifted thereby is slanted to extend downwardly and rearwardly toward the slide, and wherein the lock face on the slide is slanted at a corresponding angle to have line contact with said end portion of the lock bolt thereby releasably wedging the slide forwardly.

8. The magazine lock for a fluid powered fastener driving tool as set forth in claim 4, wherein the end portion of the lock bolt is tapered 10 to its axis and the laterally projecting axis of the cylinder and piston and of the lock bolt shifted thereby is slanted 5 from a normal to the movement plane of the slide to extend downwardly and rearwardly toward the slide, and wherein the lock face on the slide is slanted at a corresponding 15 angle to have line contact with said end portion of the lock bolt thereby releasably wedging the slide forwardly.

9. The magazine lock for a fluid powered fastener driving tool as set forth in claim 4, wherein manually engageable means is coupled to the lock bolt to retract the same.

10. The magazine lock for a fluid powered fastener driving tool as set forth in claim 4, wherein a crosshead of larger diameter than the piston couples the said piston and lock bolt and to steady the latter, wherein the frame is counterbored to slideably guide the crosshead, and wherein a compression spring pressures between the crosshead and a shoulder at the juncture of the cylinder bore and said counterbore.

11. The magazine lock for a fluid powered fastener driving tool as set forth in claim 4, wherein a crosshead of larger diameter than the piston couples the said piston and lock bolt and to steady the latter, wherein manually engageable means is accessible through at least one slot into said counterbore to retract said lock bolt, wherein the frame is counterbored to slideably guide the crosshead, and wherein a compression spring presses between the crosshead and a shoulder at the juncture of the cylinder bore and said counterbore.

12. The magazine lock for a fluid powered fastener driving tool as set forth in claim 4, wherein the fastener driving tool has an elongated grip portion spaced above and extending laterally of the head and with a strut at its remote end having supporting engagement with the housing of the magazine, and wherein the lock comprising the cylinder and piston and lock bolt is accommodated in said strut, the lock face on the slide being at the rear end portion thereof.

13. The magazine lock for a fluid powered fastener driving tool as set forth in claim 4, wherein the fastener driving tool has an elongated grip portion spaced above and extending laterally of the head and with a strut at its remote end having supporting engagement with the housing of the magazine, and wherein the cylinder bore of the lock extends through the strut with said open fluid communication into said grip portion charged therewith, the lock face on the slide being at the rear end portion thereof.

14. The magazine lock for a fluid powered fastener driving too] as set forth in claim 4, wherein the fastener driving tool has an elongated grip portion spaced above and extending laterally of the head and with a strut at its remote end having supporting engagement with the housing of the magazine, and wherein the cylinder bore of the lock extends through the strut and is slanted at an angle extending downwardly and rearwardly toward the slide and with said open fluid communication into said grip portion charged therewith, and wherein the end portion of the lock bolt is tapered and wedgedly engages the lock face on the slide.

Claims

1. A head construction and guideway closure for a fastener driving tool wherein a driver blade operates to project individual fasteners from a guideway aligned with a magazine disposed normal thereto and feeding individual fasteners into the upper portion of said guideway and wherein the lower portion of said guideway beneath said magazine is a rearwardly open channel closed by a closure positioned thereto by a slide on the magazine, and including: a tool frame having a flat bottom and having spaced depending mounting lugs with coplanar front faces normal to said bottom and having a window through the said frame and extending between said mounting lugs next adjacent to said coplanar faces thereof; a facer seated in said window and having a front wall parallel with said coplanar faces of the mounting lugs; a fastener receiving head carried by said frame and comprising, a body having a top seat engaged with said bottom and a rear face engaged with said coplanar front faces of the mounting lugs, a channel-shaped fastener guideway disposed normal to the said bottom and between said mounting lugs, and an extension projecting upwardly from the top seat of the body and engaged with said parallel front wall of the facer in said window of the frame; fastener means securing the head to said mounting lugs; a magazine slide movable in a direction normal to the rear face of the head and having a guideway closure with a front face parallel to said rear face of the head; and means releasably forcing the said magazine slide and closure positioned thereby into flat interface engagement with the said rear face of the head and closing the back of the channel-shaped fastener guideway.

8. The magazine lock for a fluid powered fastener driving tool as set forth in claim 4, wherein the end portion of the lock bolt is tapered 10* to its axis and the laterally projecting axis of the cylinder and piston and of the lock bolt shifted thereby is slanted 5* from a normal to the movement plane of the slide to extend downwardly and rearwardly toward the slide, and wherein the lock face on the slide is slanted at a corresponding 15* angle to have line contact with said end portion of the lock bolt thereby releasably wedging the slide forwardly.

14. The magazine lock for a fluid powered fastener driving tool as set forth in claim 4, wherein the fastener driving tool has an elongated grip portion spaced above and extending laterally of the head and with a strut at its remote end having supporting engagement with the housing of the magazine, and wherein the cylinder bore of the lock extends through the strut and is slanted at an angle extending downwardly and rearwardly toward the slide and with said open fluid communication into said grip portion charged therewith, and wherein the end portion of the lock bolt is tapered and wedgedly engages the lock face on the slide.