US3472440A

US3472440A - Device for driving securing elements into foundations or walls

Info

Publication number: US3472440A
Application number: US597123A
Authority: US
Inventors: Herbert Rangger; Hans-Dieter Seghezzi; Elmar Batliner
Original assignee: Hilti AG
Current assignee: Hilti AG
Priority date: 1965-12-06
Filing date: 1966-11-25
Publication date: 1969-10-14
Anticipated expiration: 1986-10-14
Also published as: NL6615816A; FR1505668A; BE690592A

Description

v I NTOFOUNDATIONS oRlwALLs Filed Nov. y25.11'966 l l `2V Shets-Sheet l FIG;

vm" 7 a, c6762 k l .zaga/VV f HERBERT musee-R HANS -D/E TER SEGHFZII B AMAR Ban/NER 4 Arranufrs Od. 14, 1,969"` v H, RANGGER` `ET AL I 3,472,440

DEVICEv FORV DRIVING SECURING ELEMENTS u INTO FOLJNDATIONS OR WALLS Filed Nov 25 1966 "FIG-ye 2 Sheets-Sheet .arromfeys United States Patent Olce 3,472,440 Patented Oct. 14, 1969 H Int. Cl. B25c 1/12, 1/14 U.S. Cl. 227--10 10 Claims ABSTRACT F THE DISCLOSURE An explosive charge operated driving tool for driving anchoring elements such as bolts, nails, etc. into a hard receiving material which includes a sleeve member which is slidable into a guide tube. An anvil member slidable in the sleeve and includes a striking head which is located outside of the sleeve in a position to be struck by an instrument such as a hammer to operate the device. The anvil member includes a portion which is engageable with the sleeve member. The anvil member moves t0 the limit of its desired movement. The anvil member includes an end with a cartridge chamber for receiving a cartridge to provide a driving force. This portion of the anvil member rides in a recess of a dry piston which is driven in the direction to the anchoring member into the receiving materials. The tube carries a safety control which includes a space member which is adapted to be interposed between the striking head and the sleeve to prevent firing of the device when the safety is set.

SUMMARY OF THE INVENTION This invention relates, in general, to devices for driving securing elements into foundations or walls and, in particular, to a new and useful setting device which is driven by an explosive charge force and to improved safety means for preventing operation thereof until the device is to be used.

The invention provides a device which includes a thrust piston having an outer end adapted to carry a bolt, nail or similar securing device and which is mounted within the device so that it will be displaced rapidly upon an explosion of a cartridge which is carried in a chamber dened in an anvil member. The anvil member is mounted in the body of the device so that it may be displaced to cause the cartridge to strike the thrust piston to eect the discharge of the cartridge. This displacement may be effected by hammer blow or a striking head portion of the anvil in order to cause a rapid displacement of the anvil against the thrust piston and ignition of the charge of the cartridge. A feature of the construction of the present invention is that a sleeve is provided around the anvil which engages the thrust piston in a limit position. The construction permits sliding movement of the anvil within the sleeve to cause the anvil to present the cartridge against the thrust piston for the discharge thereof only when a safety device is moved to a position which permits the movement of the anvil.

Prior to the present invention, apparatus of this nature was known in which there was a danger that the cartridge would be set ofi and the securing element shot outwardly from the device even upon an accidental striking of the head of the anvil.

Prior to the present invention, most of the devices includes spring arrangements which made it difficult to discharge the device by accident because the device could only be discharged by a vigorous blow on the striking head or when the apparatus was dropped from a great height. Other type locking devices have the disadvantage that the operation of the elements thereof was effected through a lever system which must be pulled up after each explosion together with the anvil absorbing the recoil force and this was extremely unpleasant to the operator and lead to unsteadiness in the use of the apparatus even during the driving process.

In accordance with the invention there is provided an apparatus for driving bolt or similar securing elements in which the cartridge may be inserted into a bearing formed in a striking anlvil and the cartridge ignited by moving the anvil toward the thrust piston which carries the bolt element to be driven in. The arrangement includes a sleeve member in which the anvil is slidable and which bears at its one end against the thrust piston. The sleeve member will permit movement of the anvil toward the thrust piston by an amount suiicient to discharge the cartridge only when a safety spacer member is removed from a location blocking the movement of the striker head portion of the anvil in a direction toward the thrust piston. In the preferred form, the spacer element is biased into a position blocking the movement of the anvil by an amount suicient to cause explosion of the cartridge and it can be moved out of this position only by operating a lever to place the apparatus in a condition ready for iring. The construction is such that the cartridge can only be ignited by manual unlocking so that dropping of the apparatus cannot release the shot. The operators hand which effects the unlocking of the safety may remain steady during the explosion, since the device may be easily gripped while the unlocking operation takes place.

In order to insure that there is always suicient spacing between the sleeve and the anvil head portion to permit a safety spacer member to enter between these two parts to lock the ready position of the anvil, spring means are provided between the anvil and the surrounding sleeve to force the anvil and the sleeve into predetermined separated positions permitting easy insertion of the spacer member. In addition, a torsion spring acts on the spacer member to tend to force it into `a locking position.

A further feature of the construction is that a control column is employed on the side of a cylindrical barrel containing the thrust piston and it provides a means for pivoting the upper part' of the body or housing -away from the lower part in order to facilitate the insertion of a cartridge into a blind bore defined at the lower en d of the anvil. With such an arrangement, it is no longer necessary for an operator to hold two diicult to handle parts since the parts will be pivoted to each other and may be easily opened or closed for the insertion of the cartridge. In addition, the construction is such that the safety condition of the spacer is effected whenever the parts are separated.

Accordingly, it is an object of the invention to provide an improved device for driving home securing elements such as bolts, nails and other fasteners which includes means for locking a striking anvil relative to a thrust piston so that the cartridge providing the explosive driving force for the thrust piston may not be exploded until a safety device is placed in a position in which it does not block one of the movable parts.

A further object of the invention is to provide a device for driving home securing elements by powder force which includes a lower separable part which carries a thrust portion and an upper part which carries an anvil having a blind bore at its lower end for the insertion of a cartridge which may be pivotally separated for the insertion of a cartridge by pivoting the upper portion on a control bolt member which is movable to displace a spacer element which will block the movement of the 3 anvil relative to the thrust piston until the device is ready for firing.

A further object of the invention is to provide a device for driving home elements into foundations and the like by an explosive force ywhich is simple in design, rugged in construction and economical to manufacture.

The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this specification. For a better understanding of the invention, its operating advantages and specific objects attained by its use, reference should be had to the accompanying drawings and descriptive matter in which there is illustrated and described a preferred embodiment of the invention.

In the drawings:

FIG. 1 is a longitudinal sectional view through a bolt setting device constructed in accordance with the invention;

FIG. 2 is a view similar to FIG. 1 with the apparatus in a ready position;

FIG. 3 is a section taken on the line III-III of FIG. l;

FIG. 4 is a section taken along the line IV-IV of FIG. 1;

FIG. 5 is a section taken along the line V-V of FIG. 1; and

FIG. 6 is a perspective view showing the uper housing part separated from the lower part for loading.

Referring to the drawings, in particular, the invention as embodied therein comprises a gun for setting securing elements such as bolts, nails, etc. into a hard material such as a concrete wall or floor. The gun comprises a body assembly which includes a guide tube or lower housing part 1 which is connected at its upper end to an upper housing part or sleeve body 11 and at its lower end to a setting or positioning element block 50. The guide tube 1 defines at its interior an expansion chamber 1a to permit expansion of the explosive gases after ignition of the cartridge. An anvil member 2 is axially slidable within limits within the guide tube 1 and it includes a piston portion 2a which is connected at its upper end to a striking head 2b and which includes a widened portion or piston 2c at its lower end. The widened portion 2c is slidable within a cylindrical recess 16 formed at the inner or upper end of a thrust piston which is slidable Within the guide 1. The lower end of the widened portion 2c of the anvil member 2 is provided with Ia cavity to receive a cartridge 17 and the cartridge is normally exploded upon relative movement of the anvil member 2 and the thrust piston 15 together to cause igniting means carried on an inner at wall 15a of the recess 16 to strike the cartridge 17 and to cause the explosion thereof.

In accordance with the invention, the anvil member 2 is surrounded by a sleeve 3 having a lower end 3a which abuts against an annular upper end 3b of the thrust piston 15. The lower end of the sleeve 3 is widened both interiorly and exteriorly to define an interior shoulder 4 which abuts against the shoulder 5' formed at the juncture of the widened piston portion 2c and the piston portion 2a of the anvil member 2. The shoulder 4 forms a stop when it abuts against the shoulder formation 5 and the contact of the end 3a of the sleeve 3 with the thrust piston end 3b prevents the anvil member 2 from being moved downwardly beyond the position indicated in FIG. 1 when the tool is in a safety condition.

The upper body portion 11 carries a sleeve element 11a which has a plurality of recesses in which are positioned balls 12 which are biased by a ring clamp or a clamping spring 13 into frictional engagement with the sleeve 3 in the manner of a friction guide.

When the instrument is to be used, a securing element, for example a bolt 52 having a pointed penetrating end and a threaded upper end, is inserted into a receiving chamber 54 defined at the lower end of the thrust piston 15. The thrust piston 15 can then be pushed backwardly in the body 50 and the guide tube 1 until it reaches the position indicated in FIG. lV in which it abuts against the lower end of the sleeve 3. In this position, the element 52 will be oriented with its tip at the outer end of the body 50. The expansion chamber space 16 which is dened between the anvil portion 2c and the thrust piston 15 cannot be shortened in the position indicated in FIG. l because the safety arrangement prevents the movement of the anvil 2 relative to the sleeve 3 so that there is no possibility that the cartridge 17 will be iired.

In accordance with a feature of the invention, the safety setting of the device is controlled by means of a control column 20 which includes an upper end 20a which is rotatably mounted within the striking head 2b and which includes a radially extending control cam portion 21 as best indicated in FIG. 3 which engages a groove 22 of the spacer member 7. The spacer member 7 is slidably mounted for radial displacement in the striking head 2b and. may be moved along a recess 8 to cause an outer end thereof to project into a space between a wall 8a of the striking head and an upper end wall 3c of the sleeve in order to prevent further relative displacement between the striking anvil 2 and the sleeve 3 when the spacer is in a safety position.

In order to change the device from the safety condition indicated in FIG. 1 to the ready condition indicated in FIG. 2, it is only necessary to rotate the column 20 by moving a lever 28 which is secured to a control sleeve 24 which is aflixed to the column in a direction from the solid line position indicated in FIG. 5 to the dotted line position. When this is done, the spacer 7 is moved outwardly from between the striking head 2b and the sleeve 3 so that these parts may be moved relatively for the purpose of causing the cartridge 17 to be brought into contact with the cartridge tiring means defined on the Wall 15a of the thrust piston 15. In FIG. 3, the parts indicated in a solid line construction show the position of these parts in the safety condition, and the dotted line position indicates the position of the parts when the device is in the ready condition, which is also indicated in FIG. 2 The axial thickness of the spacer 7 corresponds substantially to the interval indicated a between the piston portion 2b and the wall 15a of the thrust piston 15 in FIG. 1.

The control column 20 is axially displaceable within the control sleeve 24 but may not rotate in respect thereto. The control sleeve 24 is arranged in

bearings

25 and 26 for pivotal movement about an axis parallel to the longitudinal axis of the anvil 2. The

bearings

25 and 26 are secured on the guide tube 1 which includes a lateral extension 27 at its lower end. The control column 20 includes an axial groove 20b which is engaged by a nose member 24a carried by the sleeve 24 (see FIGS. 4 and 5). When the handle 28 is moved from the dotted line position to the solid line position indicated in FIG. 5, the sleeve 24 will rotate together with the control column to change the location of the spacer 7 so that it will no longer prevent the tiring of the cartridge. A torsion spring 29 which is carried in a recess in the upper housing 11 acts on the sleeve 24 to bias it into a safety position, that is, the solid line position indicated in FIG. 5, and the position of the parts indicated in FIG. 1.

In order to insure that the interval a is maintained between the piston portion 2c of the anvil 2 and the thrust piston 15, the sleeve 3 is provided with a support 30 which is mounted on an exterior ledge formation of the sleeve and which supports the lower end of a compression spring 31. The spring 31 is biased at its upper end against the striking head 2b (see FIGS. 1 and 2). The compression spring 31 presses the sleeve with its stop 4 against the ange 5' of the anvil 2. The spring 31 is strong enough to insure that the interval a will always be maintained.

As can be seen particularly from FIGS. l, 2 and 6, the end of the sleeve 24 which protrudes beyond the upper sleeve bearing 25 serves also as a pivot hearing 24b for the body portion 11 which can be turned into the position indicated in FIG. 6 when the anvil has reached the topmost position. In the closing position, the lug formations 35 on the housing part 11 will engage over the lugs 36 formed on the guide tube 1 so that a locking of both parts is insured. The parts are constructed so that the upper housing part 11 may be pivoted outwardly to disengage the lugs 3'5 and 36 to the position indicated in FIG. 6 for the purpose of inserting a cartridge in the anvil 2. The guide tube 3 and the upper housing 11 are rotatably xed together so that they will never become disengaged even in the open position.

The device is operated by rst pivoting the parts to the position indicated in FIG. '6 and inserting a cartridge into the lower end of the anvil member 2. The parts are then pivoted back again to lock them together in which case they will be always in a safety position as indicated in FIG. 1. The device 52 which is to be driven into a wall is inserted in the recess 54 of the thrust piston 15. Depending on the length of the anvil member 2 which is employed, the thrust piston will assume an axial position in the guide tube 1. If the apparatus should be dropped, such as from a ladder, on the striking head, the striking head can move only until the sleeve 3 engages the thrust piston 15, and when this occurs, there will still be at least the interval a between the anvil 2 and the thrust piston so that the cartridge cannot be red.

If it is desired to tire the device, the handle 28 is rotated to move the spacer 7 out from between the sleeve 3 and the tiring head 26. When this is done, then the interval a will not be maintained and the apparatus can be tired by striking the striker head 2b such as with a hammer. This causes the movement of the anvil 2 toward the thrust piston to present the cartridge 17 against the tiring wall 15a and the cartridge will be red. During explosion of the cartridge, the operators hand may still engage the lever 28 which will not be alected by any recoil force. The anvil 2 which absorbs the recoil slides upwardly within the guide tube 1.

In order to insure that the safety device would not become ineffective in any manner, the sleeve 24 is equipped with a pin-shaped extension 24', as indicated in FIGS. 4 and 1, which insures that there will be a pivotal movement thereof together with the sleeve 24 within a recess 11' of the body member 11. When the handle 28 is not moved out of safety position, the projection 24' will assume the position represented in FIG. 4 in dotted lines, and (when the handle is operated to release the safety, the projection will assume the position indicated in solid lines. In the solid line position, the projection will prevent the opening of the body member 11 relative to the guide tube 1 so that a cartridge cannot be inserted when the device is not set for safety. This arrangement prevents the use of the instrument without it being set intially in a safety position and it will remain in this position after the cartridge is inserted into the device. Because the nose 24' is engaged in the recess of the housing member 11, the handle 28 will always be maintained in a safety position whenever the housing member is opened to the position indicated in FIG. 6.

While a specific embodiment of the invention has been shown and described in detail to illustrate the application of the inventive principles, it `will be understood that the invention may be embodied otherwise without departing from such principles.

What is claimed is:

1. An apparatus for driving bolts, nails and similar securing devices into a hard receiving material comprising a housing including a guide tube portion, a sleeve member slidable in said guide tube portion, an anvil member having a striking head at one end located out of said housing, said anvil member being axially movable in said sleeve member and having a portion engageable with said sleeve member upon predetermined axial displacement away from said striking head for limiting axial relative movement of said anvil member and said sleeve, said anvil member having an inner piston end with means for receiving a cartridge, a thrust piston movable in said guide tube having an inner end terminating in a wall having cartridge firing means, said thrust piston having an opposite end directed out of said guide tube and said housing having means for holding the device to be driven into the hard receiving material, and a safety control carried yon said housing and comprising a movable spacer adapted to be moved between said anvil member striking head and said sleeve to prevent relative axial movement thereof beyond the movement in which said sleeve land said anvil member abut said spacer Vand a control lever pivotally mounted on said housing and being shiftable to move said spacer out of a blocking position between said striking head and said sleeve to permit said striking head to be struck to move said anvil member to cause engagement of a cartridge held thereby with said cartridge ring means to cause explosion of said charge and movement., of said thrust piston to drive the securing device into the receiving material.

2. An apparatus according to claim 1, wherein said safety control includes a sleeve rotatably mounted in said housing alongside said guide tube for rotatable movement about an axis substantially parallel to said guide tube, a control column slidable in said sleeve and connected thereto for rotation therewith, said control column having means engageable with said spacer for displacing said spacer into a blocking position between said striking head and said sleeve and out of said blocking position, said control level being connected to said sleeve for rotating said sleeve with said control column to effect displacement of said spacer.

3. An apparatus according to claim 2, wherein said housing includes an upper part which is pivotal about said control column and disengageable from said guide tube portion to permit opening of the upper end of said guide tube to permit insertion of a cartridge into said anvil member, said control column and said sleeve defining means to move said lever to a safety position when the upper part of the housing is opened.

4. An apparatus according to claim 1, wherein said safety control includes a control column rotatably mounted in said housing, said control lever being connected in said column to rotate said column, said column having a projecting cam at its upper end, said spacer having a `recess into which said cam projects, said cam being shiftable with said control column to displace said spacer.

5. An apparatus Iaccording to claim 1, including means urging said sleeve to engage said anvil member.

6. An apparatus according to claim 1, wherein said safety control includes means biasing said control lever to a position at which said device is in :safety with said spacer between said striker head and said sleeve.

7. An apparatus according to claim 1, wherein said safety control includes a control sleeve rotatably mounted on said housing for rotation about an axis substantially parallel to said anvil member and a control column carried by said sleeve and rotatable therewith for displacing said spacer, said housing including upper and lower portions, said upper portion being pivotal about said sleeve to open said device for exposing the lower end of said anvil to permit insertion of a cartridge.

8. An apparatus according to claim 1, wherein said striker head has a center of gravity which is aligned with the axis of symmetry with said anvil member.

9. An apparatus according to claim 1, including means urging said sleeve to engage said anvil member, said safety control including a control sleeve pivotally mounted in said housing adjacent said anvil member and having a control cam thereon which is engageable with said spacer for shifting said spacer into and out of engagement between said striker head and said sleeve member, said control lever member being connected to said control sleeve, means biasing said control sleeve with said lever member to position said lever member against said housing in a safety position with said spacer located between said striker head and said sleeve member, said housing including an upper portion and a lower portion, said upper portion being pivotal about said control sleeve to separate said upper portion from said lower portion for insertion of said cartridge in said anvil member, said thrust piston inner end having a recess into which said anvil is movable, said Wall with said cartridge ring means being on the inner end of said recess.

10. An apparatus according to claim 9, wherein said control sleeve includes a projection which rides in a recess 8 of said housing, said projection being engageable with the upper portion of said housing to move said control sleeve with said lever member to a safety position when said upper portion is opened.

References Cited GRANVILLE Y. CUSTER, JR., Primary Examiner