US2787000A

US2787000A - Stud driving tool

Info

Publication number: US2787000A
Application number: US124078A
Authority: US
Inventors: Traver J Smith; Ralph K Daugherty
Original assignee: OREGON SAW CHAIN CORP
Current assignee: OREGON SAW CHAIN CORP
Priority date: 1949-10-28
Filing date: 1949-10-28
Publication date: 1957-04-02
Anticipated expiration: 1974-04-02

Description

April 2, y1957 T. JfsMm-i ETAL April 2, 1957 T. J. SMITH ErAL snm DRIVING TooL Filed Oct. 28, 1949 4 Sheets-Sheet 2 s. W www r m w m5@ d V// Tow April 2, 1957 1r. J. SMITH ET AL STUD DRIVING ToorJ 4 Sheets-Sheet 3 Filed Oct. 28, 1949 IIIIE ,ZMJ my n mm/W N N d an 5.44m NJ. Ir W10 mw .IP Y, B

AApril 2, 1957 T. J. sMn-H ET AL STUD DRIVING TOOL Rled Oct. 28, 1949 4 Sheets-Sheet 4 United States Patent O STUD DRIVING TOOL Traver I. Smith and Ralph K. Daugherty, San Jose, Calif., assignors, by mesne assignments, to Oregon Saw Chain Corp., Portland, Oreg., a corporation of Oregon Application October 28, 1949, Serial No. 124,078

27 Claims. (Cl. 1--106) The present invention relates to tools for driving studs into walls such as concrete and into steel structure by means of an explosive action and is concerned more particularly with a tool of above character which is constructed for safe operation, for ease of tiring, and which tends to reduce the amount of skill required in the operator employing the tool. The tool structure is such that two inoperable halves are provided when the tool is broken into two halves for loading and is such that unintentional loading of the tiring pin spring ifs not likely to occur.

The invention is also concerned with a -tool of the above character in which the barrel can be extended into recessed places such as junction boxes, for example, and can be fired with the same safety as when placed directly against 'a plane surface. The tool is also designed to provide a safe tiring construction and mode of operation by eliminating the necessity for movement of a portion of the tool toward the surface into which the stud is to be driven at the time of firing and this is accomplished in part by the sequence of push and turn movements to elfect the tiring of the tool. The tool is designed to be taken apart easily without the aid of special tools.

The above and other objects of the invention are attained in the embodiment described herein in connection with the accompanying drawings in which:

Figures la and 1b are a longitudinal sectional view through the tool with the parts in their normal position prior to any operation of the tool.

Figures 2a and 2b are views similar to Figures la and lb in which the tool has been compressed preparatory to firing but has not had any relative turning movement applied to effect the tiring operation.

Figure 3 is an elevational view of the tool partially in section to illustrate certain details of construction.

Figure 4 is a plan view of the pressure pad employed with fthe tool.

Figure 5 is a detailed view of the breech block of the tool.

Figure 6 is a detailed view of the firing control cam of the tool as viewed from the bottom on the line 6-6 in Figure la.

Figure 7 is ya transverse sectional view taken as indicated by the line 7--7 in Figure la showing the sear type trigger and its mounting.

Figure 8 is a fragmentary sectional View of the tool taken -as indicated by the line 8 8 in Figure 2a, with the grip or handle 11 omitted from the view.

Figure 9 is a sectional view similar to Figure la showing the rear or handle half of the tool.

Figure l0 is a sectional view similar to Figure lb showing the front or barrel half of the tool.

Referring to Figures la, lb, and 3, the tool includes a cylindrical housing 10 having an end hand grip or handle 11 and an intermediate hand grip 12 secured thereon as later described. Disposed within the housing is a firing control cam 13 of generally cylindrical shape, and a breech block or firing pin carrier 14 for a firing pin 16.

2,787,000 Patented Apr. 2, 1957 ICC The breech block 14 is connected at its forward end to the barrel 17 there being a removable breech plug 18 clamped therebetween and a hardened barrel liner 19 pressed in the barrel for holding the stud 21 to be driven. The cartridge is shown at 22 in the breech plug. About the barrel 17 there is a barrel guide sleeve 23 between which and a snap ring 24 the barrel spring 26 is disposed. A firing pad 27 is provided about the muzzle of the barrel being mounted on a sleeve 28 having a spring 29 associated therewith. A shell or housing sleeve 31 encloses the spring 29 and associated parts and is connected to the housing 10 as later described.

Referring in detail to the construction of the above parts, the housing 10 at its rearward or left end, as viewed in Figure la, frictionally receives the rear grip or handle 11 which h-as integrally molded therein a sleeve 36 provided with a shoulder 37 engaging the end of the housing 10. An aperture 38 in the rubber portion of the grip 11 and in the sleeve 36 register with a circumferential slot 35 (Figures la, 2a, and 8) in the housing 10 to provide for insertion of a retaining screw 39 which is threaded into the cam 13. The screw 39 connects the grip 11, the housing 10, andthe cam 13 against relative longitudinal displacement while providing for relative rotative adjustment between the housing 10 and Ithe grip 11 and between the housing 10 and the cam 13. Within the recessed end of the housing 10, there is provided a guide plate 41 secured in place by a snap ring 42 of rectangular cross section, the guide plate having an ear 43 at the lower end for engagement ina longitudinal milled groove 44 (Figure 3) of the housing 10 to maintain the alignment of the guide plate 41. The guide plate 41 is apertured to slidably receive the rear end of the tiring pin 16 and to provide a stop for the actuating spring 46 therefore which extends forwardly and abuts a snap ring 47 on the firing pin. The forward end of the firing pin 16 is slidably mounted in Ka bored passage 48 in the breech block 14, which passage terminates in a tapered end seat 48a to correspond to the tapered end of the ring pin itself thus providing a stop for forward movement of tiring pin as later described. Adjacent its front end the firing pin 16 is provided with an annular groove 49 for engagement by a sear type trigger 51 (Figures 1a and 7), which is pivoted on a pin 52 in the breech block and which is disposed in a milled transverse slot 53 of the breech block. The trigger 51 is spring-urged to the position shown in Figure 7 and for this purpose is en gaged by the end of a flat spiral spring 54 which extends around an annular groove 56 in the breech block and is secured thereto by a pin 57. As seen by comparison of Figures 2a and 9, rearward movement of the breech block 14 will engage notch 55 of the control cam 13 with the upper end of the trigger 51 so that subsequent relative rotation between the breech block 14 and the cam 13 will operate the trigger as later described.

' The breech block 14 (Figure la) is provided with a transverse aperture 58 to receive snugly Ia guide pin 59 having an end slidably engaged with the milled groove 44 in the housing 10 so that the breech block is constrained` portion of the cam groove 62 is provided with an en' larged end portion 62a which permits relative turning movement between the control cam 13 and the breech block 14, which occurs, as later explained, at the time of firing torelease the ring pin 16 from the trigger 51.

To connect the breech block 14 to the barrel 17 at the midpoint of the tool so as to provide two inoperable portions of the tool when disassembled, the breech block has an internally threaded recessed end -66 (Figures la and 9) which engages over an enlarged threaded portion 67 (Figures la and l0) of the barrel with a tapered flange 68 of the breech plug 18 interposed therebetween. The breech plug 18 seats against ya tapered surface of the barrel with its end spaced from the barrel liner 19 to provide clearance V'for sa flange on the head 71 of the stud 21.

The hand grip V12 has molded therein a ring 74 carryin g a pair of diametrically opposite connecting pins 76 which extend into aligned slots 77 in the housing 10 (Figure 9). A snap ring 7S is seated within the housi-ng and-engages the pins 76 to maintain the assembled Vcondition of the parts.v In this way, the housing 10 (and the breech block "-14 because of the engagement of its pin 59 with a groove 44 of the housing 10) are connected for rotative movement as a unit with the grip 12. It will be noted also that the snap ring 7S forms a stop (Figures la and `9) for the breech block 14 in the normal expanded position of the parts, in which the breech block is urged forwardly by the ring pin spring 46 acting through the ring pin 16 and the trigger 51 and also urged forward by the spring 26 acting through the barrel 17.

It should be noted also that the parts thus far described in detail, with exception of the barrel 17, form the breech or rear .portion of the tool which are assembled as a rear unit separable from the front end or barrel portion of the tool, now to be described.

The barrel 17 is slidably and non-rotatably mounted within the barrel guide sleeve 23 which is held in place within the shell 31 at one end thereof by a snap ring 72 and by respective diametrically opposed pins 70 seated in the sleeve 23 and engaging suitable apertures in the shell 31. For this purpose, the barrel 17 is provided with a longitudinal groove 82 which is engaged by a guide pin 81 securedin the barrel guide sleeve. The snap ring 24 and a washer 80 at the end of the barrel guide sleeve 23 provide abutments for the barrel spring 26.A The spring 26 maintains the barrel guide lsleeve in engagement with the snap ring 72, previously referred to, so that the barrel and the barrel guide sleeve are in normally relatively expanded relation as seen in Figures la and 1b.

In order to control the movement of the deector pad 27 with respect to the barrel, the deector control spring 29 is seated at `one end against a shoulder'S- of the barrel guide sleeve 23 and at the other end engages the end of the deector mounting sleeve 28. The sleeve 28 is slidably mounted within the shell 31 with a close sliding fit and abuts a retaining nut 86 threaded in the end of this shell in the expanded positionV of the spring shown in Figure `1b. At its outer end the deflector mounting sleeve 2S is provided with a reduced threaded portionV 87 for receiving the central eccentric control plate 88 of the deector pad 27, which is rotatively adjustable within the outer support plate 39 of this. pad. The adjustable plate S8 is provided with an external annular flange 91 which seats in a cooperating recess of the plate 39 and is held therein by a retaining plate 92. Respective rubber parts '93 and 94 are suitably secured to the plates 89 and 38' for engagement with the surface against which the tool is to be tired to install a stud. The deflector padstructure is disclosed and claimed in the co-pending application of Virginius R. Erickson and :Benjamin B. Bullwinkle, Serial No. 130,818, itiled December 2, 1949 for Stud Driving Tool, now Patent No. 2,679,645 granted v.lune 1, 1954.

From the above description, it will be apparent that the tool can be 'separated into two Vhalves by grasping the hand grip 12 and the shell 31 to unscrew the barrel from the breech block so that the stud 21 and the cartridge 22 can be placed in the tool'for operation indriving a stud. With the stud and the cartridge in place as shown in Figures la and 10 and the tool placed with the barrel against the surface into which the stud is to be driven, subsequent pressure on the handle 11 or the handle 12 will move the parts from the position shown in Figures 1a and 1b to the position of the parts shown in Figures 2a and 2b where the barrel has receded (or the housing has telescoped over the breech block and barrel structure) until the deflector pad has engaged the surface into which the stud is to lbe driven and in which the spring -46 for the tiring pin 16 has been compressed. This receding movement of the barrel 17 and with it the breech block 14, also brings the end of the trigger 51 into engagement with its control slot 55 in the cam cylinder 13 and has disposed the roller 61 into circumferential alignment with the enlarged portion 62a (Figure 6) of the cam groove 62 of the cam cylinder 13. Then by gripping with one hand the grip 11 and with the other hand the grip 12 and relatively rotating the grip 11 and cam cylinder 13 as a unit, with respect to the breech block 14, the housing 10, and the grip 12, as a unit, the trigger S1 is moved out of engagement with the tiring pin groove 56 so that it is free to move forward under the influence of its spring 46 and lire the cartridge 22 in the usual fashion. Thus, the trigger 51 forms a part of control means for tiring operation and has two actively adjusted positions with respect to the firing Vpin `16, in one of their relative positions it restrains movement of the iin'ng pin under the urgency of the spring 46 during receding movement of the breech block 14 and the barrel 17. After the receding movement is completed, the vhand grip 11 Vis turned to move the trigger 51 to a second relatively adjusted position with respect to the firing pin 156, in which the tiring pin is free of restraint, and tiring action is effected. This results in shearing the flange on the head 71 of the stud 21 and driving the stud 21 into the surface with which the tool has been engaged. After 'the tool has been red, the reverse movement of the parts takes place to restore the various parts to the positions shown in Figures la and 1b. By virtue of the relative telescoping movement of the deector pad in its mounting with respect to the barrel, the barrel can be extended into recesses into engagement with thesurface therein while the deector pad is engaged with the surface around the recess. That is, if an extension of the .barrel is necessary to reach into a recess, the deflector pad engages about the recess and recedes with respect to the barrel until the end of the barrel engages the surface into which the fastener is to be driven. The extreme position of the deector pad `with respectto the barrel is shown in Figure 2b. It will be noted that the amount the barrel extends beyond the deector pad, in the normal position of the parts shown in Figure 1b, is substantially less than the amount of travel required yto engage ythe roller 6'1 with the enlarged portion 62a at the rear of the cam slot 62 so that the pressure pad is always firmly engaged with the surface about the barrel at the time of ring and must also have some relative receding movement with respect tothe shell 31 in the conditioning of the tool for firing. Because of the close sliding fit between the deector'mounting sleeve 2S, the shell 31, and the nut S6, any substantial tilting of the deflector pad 27 with respect to the surface of the work will resultv in binding the parts and preventing further telescoping movement of the detiector pad'so that the tool cannotbemoved to tiring position -unless in substantially right angle relation to the surface into which the stud is to Vbe driven. This is an important safety factor of thetool in that any substantial amount of tilting the tool with respect to the surface is apt to result in ricocheting of the stud as it engages the surface which itis supposed to penetrate.

It will be noted also that 'the construction ofthe tool lends itself to ease of assembly and disassembly with minimum of tools required, the entire disassembly ct 'the tool beingreffected by the vremoval of the screw 39 and the various snap rings which hold the parts in place, together with the removal of the deflector pad from its mounting sleeve 28.

As previously explained, when the tool is separated in the two halves as illustrated in Figures 9 and l0, there is no means present by which the firing pin spring 46 can be compressed so that no accidental preloading of the firing spring can take place until the tool is assembled and ready to fire. Also by virtue of the fact that the cartridge is carried in one half of the tool and the tiring pin in the other half the two halves of the tool by themselves are inoperable and no accidental firing can take place in this respect.

Further insurance against accidental or unintentional firing is obtained through the sequence of movements of the tool to obtain firing, i. e., the rearward and front sections must be relatively telescoped by pressing action of the tool against the surface to move the parts from the position shown in Figures la and 1b to that shown in Figures 2a and 2b and then a definite turning movement must be applied between the control cylinder 13 and its grip 11 and the breech block 14 and its grip 12 in order to produce the actual firing of the tool. At the time of firing there is no relative movement of any part of the tool toward the surface so that the tool is firmly in place and any tendency toward misalignment of the tool with respect to the surface can be avoided so that a better penetrating section is obtained with less shattering of the material around the point of penetration of the stud.

Referring to Figure 2a, it will be noted that at the time of firing, the firing pin carrier 14 is positioned against the forward end of the cam cylinder 13 so that recoil is transmitted directly, with no interposed springs, through the housing to the grip 11. This results in a complete absorption of recoil by the operator with reduced tendency of the tool to be moved out of position at the time of firing.

While we have shown and described a preferred embodiment of the invention, it will be understood that the invention is capable of variation and modification from the form shown so that its scope should be limited only by the scope of the claims appended hereto.

We claim:

1. In a tool for explosive driving of studs, a cylindrical housing, a hand grip mounted at the rearward end of said housing for relative rotative movement with respect thereto, a control cylinder mounted within said end of said housing and connected to said hand grip for rotative movement therewith, said cylinder 'having a notch at its forward end and having a cam slot extending from said forward end to a rearward enlarged slot portion, a breech block slidably and non-rotatably mounted in said housing and normally spaced forwardly of said cylinder, a ring pin in said breech block, a trigger latch for said firing pin carried by said breech block and having a portion in longitudinal alignment with said notch and for engagement `therewith upon rearward movement of said breech block, said breech block having a guide portion engaging said cam slot for preventing relative rotative movement between said block and said cylinder except when engaged 'with said enlarged slot portion, a barrel detachably engaged with said breech block, a barrel guide sleeve disposed about said barrel and having a slidable non-rotatable connection therewith, a barrel spring, a shell disposed about and connected to said guide sleeve, a de- 'ector pad disposed about the muzzle end of said barrel, 'a mounting sleeve carrying said pad and extending inwardly within said shell, a stop for said mounting sleeve in said shell, and spring means interposed between said mounting sleeve and said guide sleeve.

2. In a tool for explosive driving of studs, a cylindrical housing, a hand grip mounted at the rearward end of said housing for relative rotative movement with respect thereto, a control cylinder mounted within said end of said housing and connected to said hand grip for rotative movement therewith, a breech block slidably and non-rotatably mounted in said housing and normally spaced forwardly of said cylinder, a firing pin in said breech block, a trigger latch for said ring pin carried by said breech block, said control cylinder having notch means for engaging said latch and effecting release thereof upon relative longitudinal movement of said cylinder and said breech block followed by relative rotative movement therebetween, a barrel detachably engaged with said breech block, a barrel guide sleeve disposed about said V barrel and having a slidable non-rotatable connection therewith, a barrel spring guide, a shell disposed about and connected to said guide sleeve, a deiiector pad disposed about the muzzle end of said barrel, a mounting sleeve carrying said pad and extending inwardly within said shell, a stop for said mounting sleeve in said shell, and spring means interposed between said mounting sleeve and said guide sleeve.

3. In a tool for explosive driving of'studs, a cylindrical housing, a hand grip mounted at the rearward end of said housing for relative rotative movement with respect thereto, a control cylinder mounted within said end of said housing and connected to said hand grip for rotative movement therewith, said cylinder having a notch at its forward end, a breech block slidably and non-rotatably mounted in said housing and normally spaced forwardly of said cylinder, a firing pin carried by said breech block and in said breech block, a trigger latch for said firing pin having a portion in longitudinal alignment with said notclc and for engagement therewith upon rearward movemen of said breech block, means for controlling relative ro tative movement between said block and said cylinder, z barrel detachably engaged with said breech block, a barre guide sleeve disposed about said barrel and having a slidable non-rotatable connection therewith, and a barrel spring connected between said barrel and said housing and resisting inward movement of the barrel with respect to said housing.

4. In a tool for explosive driving of studs, a cylindrical housing, a hand grip mounted on an end of said housing for relative rotative movement with respect thereto, a control cylinder mounted within said end of said hous- Aing and connected to said hand grip for rotative movement therewith, said cylinder having a notch at its forward end, a breech block slidably and non-rotatably mounted in said housing and normally spaced forwardly of said cylinder, a ring pin in said breech block, a trigger latch for said firing pin carried by said breech block-and having a portion in longitudinal alignment with said notch and for engagement therewith upon rearward movement of said breech block, means for controlling relative rotative movement between said block and said cylinder, a barrel detachably engaged with said breech block, a barrel guide sleeve disposed about said barrel and having a slidable non-rotatable connection therewith, and a barrel spring connected between said barrel and said housing and resisting inward movement of the barrel with respect to said housing.

5. In a tool for explosive driving of studs, a housing structure, a barrel assembly slidably mounted with respect thereto, spring means maintaining a normally expanded condition of said assembly with respect to said housing, deflector means surrounding the muzzle end of said barrel, and means mounting said deliector means for yieldable receding movement with respect to said muzzle end.

6. In a tool for explosive driving of studs, a housing structure, a barrel assembly slidably mounted with respect thereto for movement from a normal position to a ring position, spring means maintaining a normally expanded condition of said assembly with respect to said housing and said assembly receding into said housing to firing position, deflector means surrounding the muzzle end of said barrel, and means mounting said defiector means for yieldable receding movement with respect to said muzzle end, said mounting means providing for a greater extent of receding movement of said d'eector means than that-of said assembly.

7. In a tool for explosive driving of studs, a housing structure, a barrel assembly slidably mounted with rcspect thereto, spring means maintaining a normally cxpanded condition of said assembly with respect to said housing, deiector means surrounding the muzzle end of said barrel, andmeans mounting said defiector means for yieldabl'e receding movement with respect to said muzzle end, said mounting means including telescoping parts having a'close sliding tit to bind under angular stresses applied -to said Ydeilector means. Y

-8. VIn a tool for explosive driving of studs, Va housing structure, Va barrel assembly slidably mounted with respect thereto, spring means maintaining a normally expanded condition of said assembly with respect to said housing, deiiector means surrounding the muzzle end Vof said barreLand means mounting ,said detlector means `for yieldable receding movement with respect to said muzzle end, said mounting Vmeans 'including .means for stopping relative sliding movement between said barrel and said deflector means when angular stresses are applied to said deector means.

9. In a tool for explosive driving of studs, a housing, a breech block and barrel `structure mounted for longitudinal sliding movement in .the housing between a projecting position and a retracted position, .a tiring pin in the breech block Aof Ysaid'structure, a tiring pin spring energized by movement of said structure from said projecting position to said retracted position, a trigger latch for `said tiring pin movably mounted in Vthe breech block of said struct-ure and normally engaging said pinto restrain 'firing movement thereof during energization of said spring, a latch releasing'member in said housing and vspaced from said latch to provide for rotative driving engagement therebetween upon receding movement o'f said structure to said retracted position in said housing, said structure and saidhousing having a lost-motion connection with said latch Yreleasing member in said retracted position providing lfor relative rotative movement thereof with respect to said latch releasing member to etect rclease of said latch.

l0. In a tool for explosive driving-of studs, a housing, a breech block and barrel st-ructure mounted for longitudinal sliding movement in the housing, said breech block and lbarrel structure being movable -from a normal expanded position with respect to said housing by receding movement to a retracted position in said housing, a tiring pin in said structure, a vnormally inactive spring means for said tiring pin, a trigger latch in said structure and normally engaging said ring pin and preventing movement of said tiring pin under the urgency of said spring means, a latch releasing member in said housing and spaced from ,said ,latch to provide ,for envgagement therebetween upon receding movement of said .structure into said housing, said spring means being cornpressed 'by said receding movement, said structure `and said housing being connectedfor relative rotative .movement -with respect to'saidlatch releasing member in the relative longitudinal retracted position `thereof with said latch releasing member and said -latch engaged to effect Vrelease of said latch.

1l. In ka tool for explosive driving of studs, a houszing, a breech block and ,barrel structure mounted yfor longitudinal sliding movement in the housing, saidbreech block and barrel structure being movable from a normal expanded position with respect .to said housing by receding movement to a retracted position in 'said housing, a tiring pin in said structure, a latch in said structure and Vnormally .engaging said tiring V,pin and preventing move- Vment of said firing pin, a latch releasing member in said housing and spaced from said latch to Aprovide for `en .gagement` therebetween upon receding movement Aof said structure into said housing, said structure being con. nectd for relative rotative movement withy respect to said latch releasing member in the relative longitudinal retracted position thereof with said latch releasing member and said latch engaged to effect release of said latch.

l2. in a tool for explosive driving of studs, a housing, a breech block and barrel structure mounted for lon- Vgitudinal sliding movement in the housing, and normally maintained in expanded relation thereto, a Iiring pi in said structure, normally ineffective means for control'- ling operation of said tiring pin, means responsive to receding movement of said structure with respect to said housing to condition said operation controlling means for operation, and means mounted for rotary movement on said housing for effecting operation of said operation controlling means.

13. in a tool for explosive driving of studs, a housing, a breech block and barrel structure mounted for longitudinal sliding movement in the housing, and normally maintained in expanded relation thereto, a tiring pin in said structure, normally 'ineiective spring means for operating said firing pin, normally active latch means for said tiring pin, means` responsive to lrecedingmovement of said structure for loading said spring means, and manually operable means for releasing said latch.

14. In a tool for explosive driving of studs, a housing, a breech Vblock and barrel structure mounted for llongitudinal sliding movement in the housing from a normal expanded position to a retracted position, a normally deenergized tiring means in said structure said breech block and barrel structure energizing said firing means upon movement from said expanded position to said retracted position, a firing control cam for said iir'ing means mounted for limited rotary movement in said housing, a rst grip journalled on said housing and connected to said control cam, and a second grip secured to Y said housing, said grips providing means for eecting relative turning of said cam with respect to said housing and said structure to cause operationof said firing means.

15. In a tool for explosive driving-of studs, a housing, a breech "block and barrel structure mounted for longitudinal sliding movement in the housing between a normal expanded position and a retracted position, a normally de-energized tiring means in said structure, said firing means being connected for energization upon movement of said structure from said expanded position to said retracted position, a firing control cam for said tiring means mounted vfor .limited rotary movement in said housing to control operation of the said tiring means,

.and a gripkjournalled on said housing and connected to said control cam.

16. In a to'ol for explosive driving of studs, a housing, a breech block and barrel structure mounted for longitudinal sliding movement in the housing between a normal expanded position and a retracted position, a normally de-energized tiring means in said structure including a ring pin having a shoulder and normally deenergized spring means engaged withsaid pin, Asaid spring means -bein'g connected for energization upon lmovement of said structure' from said expanded vposition to said retracted position, a latch lever pivoted about a longitudinal axis .and spring-urged to engage said shoulder, a tiring control cam for said .ring' Ameans mounted for limited rotary movement in said housing .to control operation of said ring means, and a grip journalled on said housing and connected to said control cam.

17. In a tool for explosive driving of studs, al housing, a breech block and barrel structure mounted vfor longitudinal sliding movement in the housing between a normal expanded position and a retracted position, a normally de-energized ring means insaid structure, said Vtiring means lbeing connected to said -structure andsaid housing for energi-zation uponv movement fof said v'structure from expanded position to said retracted position, a tiring control cam rotatably mounted in said housing, and

grip means carried by said housing and connected to said control cam to control rotation of said cam to cause operation of said firing means after energization thereof.

18. In a tool for explosive driving of studs, a housing, a breech block and barrel structure mounted for longitudinal sliding movement in the housing between a normal expanded position and a retracted position, a normally de-energized ring means in said structure, said firing means being connected to said structure and said housing for energization upon movement of said structure into said housing, ring control cam rotatably mounted in said housing, and grip means carried by said housing and connected to said control cam to control rotation of said cam to cause operation of said ring means after energization thereof, the sliding receding movement of said structure into said housing to said retracted position serving to place said structure in endwise engagement with said cam for transmission of recoil therethrough to said housing and said grip means upon operation of said firing means.

19. In a tool for explosive driving of studs, a housing, a breech block and barrel structure mounted for longitudinal sliding movement in the housing from a normal expanded position to a retracted position with respect thereto, a ring pin mounted for longitudinal sliding movement in said structure, a ring pin spring interposed between said pin and a rearward portion of said housing, said spring being relatively de-energized in said expanded position of said structure with respect to said housing, a latch element movably mounted on said structure and engaging means on said firing pin to restrain tiring movement thereof upon receding movement of said structure into said housing to said retracted position, a control member mounted in said housing for limited rotary movement with respect thereto and having means for establishing driving engagement with said latch element upon movement of said structure to its retracted position, and means interconnecting said structure and said member to prevent relative rotary movement therebetween in the expanded positon of said structure with respect to said housing, said interconnecting means having a lostmotion connection in said retracted position of said structure to provide for rotary movement of said control member with said latch element engaged therewith to disengage said latch element from said tiring pin.

20. In a tool for exxplosive driving of studs, a housing, a breech block and barrel structure mounted for longitudinal sliding movement in the housing from a normal expanded position to a retracted position with respect thereto, a firing pin mounted for longitudinal sliding movement in said structure, a firing pin spring interposed between said pin and a rearward portion of said housing, said spring being relatively de-energized in said expanded position of said structure with respect to said housing, a latch element movably mounted on said structure and engaging means on said ring pin to restrain firing movement thereof upon receding movement of said structure into said housing to said retracted position, a control member mounted in said housing for limited rotary movement with respect thereto and having means for establishing driving engagement with said latch element upon movement of said structure to its retracted position, means interconnecting said structure and said member to prevent relative rotary movement therebetween in the expanded position of said structure with respect to said housing, said interconnecting means having a lost-motion connection in said retracted position of said structure to provide for rotary movement of said control member with said latch element engaged therewith to disengage said latch element from said firing pin, and a grip mounted for movement in said housing and connected to said control member for effecting said limited rotary movement thereof.

2l. In a tool for explosive driving of studs, a housing, a breech block and barrel structure mounted for .4 i 10 y y longitudinal sliding movement in the housing and normally maintained in expanded relation thereto, a ring pin, normally inactive spring means for operating said ring pin, means responsive to receding movement of said structure for loading said spring means, and means including a hand grip mounted for rotary movement on the housing relative to said structure for rendering said spring means effective after loading thereof.

22. In a tool for explosive driving of studs, a housing, a breech block and barrel structure mounted for longitudinal sliding movement in the housing and normally maintained in expanded relation thereto, a hand grip on said housing at the end thereof opposite to the barrel end of the tool, said hand grip being mounted for limited rotative movement, a tiring pin, normally ineffective means for controlling operation of said firing pin, means responsive to receding movement of said structure with respect to said housing to condition said operation controlling means for operation, and means responsive to rotary movement of said hand grip relative to said structure for eifecting operation of said operation controlling means.

i 23. In a tool for explosive driving of studs including a barrel part and a handle part, a breech block in said handle part mounted for longitudinal sliding movement therein, a barrel in said barrel part detachably connected to said breech block, whereby in the assembled condition of the tool said breech block land said barrel are slidable as a unit with respect to the handle part, means normally maintaining said breech lblock and said barrel in expanded relation relative to said handle part, a cam cylinder in said handle part having a cam slot, means on said breech block engaging Isaid cam slot for controlling relative turning movement therebetween, a tiring pin in said handle part, a firing pin spring, means responsive to receding movement of said barrel and said breech block to place |said spring under compression and thereby condition the tiring pin for firing, a hand grip mounted for limited rotative movement on said handle part, 'and means controlled by said hand grip upon rotative movement thereof, with said barrel and `said breech 'block in receded position and with said firing pin yspring under compression, to release said firing pin for firing action under the urgency of said firing pin spring.

24. In a tool for explosive driving of studs including 'a Ibarrel part and a handle part, a breech block in said handle part mounted for longitudinal sliding movement therein, a barrel detachably connected to said breech block, whereby in the assembled condition of the tool said breech block and `barrel are slidable as `a unit with respect to the handle part, means normally maintaining said breech block and said barrel in expanded relation relative to said handle part, a firing pin in said handle part, a firing pin spring, control means carried 'by said breech block and having one position with respect to said ring pin in which said means is effective to restrain firing movement of said pin during receding movement of said barrel and said breech block to place said spring under compression and condition it for firing, and said control means having a second position with respect to Isaid tiring pin in which said means is ineffective to restrain said pin, a hand grip mounted for limited rotative movement on said handle part, and means controlled by said hand grip upon rotative movement thereof, with said barrel and said breech block 'in lreceded position and with said firing pin spring under compression, to effect relative movement between said control means and said firing pin to move said control means from said one position relative to said ring pin to said second position to release said ring pin for firing action under the urgency of said tiring spring pin.

25. In a tool for explosive driving of studs, a housing, a breech block and barrel structure, said structure having its breech end positioned within said housing, a deflector pad structure surrounding the muzzle end of said barrel, one of said structures being mounted for longitudinal slidingmov'ement withl respect tosaid housing and normally maintained inY ep'andedgreltion thereto, a iring pin having an end in `said breech block, normally ineiective 'spring means for operating said firing pin, normally active latch means for saidring pin, means responsive Yto receding movement of said one of said structures with respect to said housing ,for loading said spring means, and manually `operable means for releasing said latch. A

26. Ina tool for explosive driving fof studs, a housing, a breech block ,and barrel structure .having a breech end and a muzzle end, said breech .end of saidstructurebeing positioned withinsaidjhousing, va:.le'flector pad y structure surrounding the muzzle .end of the first mentioned struc-r ture, one of said structures being mounted lfor llongitudinal sliding movement relative to said housing between' an extended .position and a vc oimare'ssed.gposition, `resilient means urging said one` structure toward said extended position, a firing pin having an end in said breech block, a normally unloaded springlmeans for operating said firing lpin, normally act-ive latch means yfor preventing operation of said tiring pin, means including said latch for loading said springlmeans upon movement of vsaid one structure from jsaid extended position to said compressed position, and manually opera-ble means operable when said one structure is in said compressed position only for releasing said latch. Y

27. In a tool for explosive driving `of studs, a housing, a breech Iblock and 'barrel structurehaving a breech end and 4a rin'uzzleY end, said breech endv of said structure-being positioned within'sa'idV housing, a de'ectorpad structure surrounding the muzzle end of said `breech block and barrel structure, :one `of said structures being mounted for longitudinal sliding movement relativerto said housing 'between an extended position and a compressed position, resilient means urging said one *structureV toward said extended position, a ring pin movable 'between -a retracted `and a tiring position, normally unloaded spring means for moving said Lpin from retracted to firing position, 'a latch moved by said onestructuije andengaging `said pin to move said pin to retracted position 'and load said spring means upon movement of said one structure from said extended :position to said compressed position and manually opera-ble means .positioned to engage said. latch when said one structure is in said compressed position `only for rreleasing said latch to lenablesaid spring means to move said pin to ring position.

References Citedvin the .le of this patent UNlTED STATES PATENTS Temple Apr. 6, 1943