US3052099A

US3052099A - Fastener applying tool and power unit therefor

Info

Publication number: US3052099A
Application number: US729349A
Authority: US
Inventors: George J Van Hecke
Original assignee: Huck Manufacturing Co
Current assignee: Huck Manufacturing Co
Priority date: 1958-04-18
Filing date: 1958-04-18
Publication date: 1962-09-04
Anticipated expiration: 1979-09-04

Description

Sept. 4, 1962 G. J. VAN HEcKE FASTENER APPLYING TOOL AND POWER UNIT THEREFOR Filed April 18, 1958 5 Sheets-Sheet 1 e. 2S. O/MW me N EH M M ,i f, e @Y MB /J/ w L d l y Sept. 4, 1962 G. J. VAN HECKE 3,052,099

FASTENER APPLYING TooL AND POWER UNT THEREFOR Filed April 18, 1958 5 Sheets-Sheet 2 INVENTOR.

E@ fm Sept' 4, 1962 G. J. VAN HECKE 3,052,099

FASTENER APPLYING TOOL ND POWER UNIT THEREFOR Filed April 18, 1958 5 Sheets-Sheet 3 INVENTOR. @607e .f' l/arr Hee/fe.

Sept- 4, 1962 G. J. VAN HECKE 3,052,099

FASTENER APPLYING TOOL AND POWER UNIT THEREF'OR Filed April 18, 1958 5 Shee'cs-SheecI 4 INVENTOR. @Gaye j' [Q77 #9c/ge.

BY //VJAJ, L

,y formar/s:

Sept. 4, 1962 G. J. VAN HECKE FASTENER APPLYING TooL AND POWER UNIT THEREFOR Filed April 18, 1958 5 Sheets-Sheet 5 ,ffii

gov-t army/s.

INVENTOR. )QW Hee/fc BY fr United ,t States Patent Oilce 3,052,099 Patented Sept. 4, 1962 3,052,099 FASTENER APPLYING T001. AND PWER UNIT THEREFR George J. Van Hecke, Detroit, Mich., assigner to Huck Manufacturing Company, Benoit, Mich., a corporation of Michigan Filed Apr. 1S, 1958, Ser. No. '729,349 13 Ciaims. (Ci. 60--S4.5)

This invention relates generally to mechanisms for applying fasteners and more particularly to a fastener applying tool and a hydraulic power unit for a fastener drivmg tool.

The fastener applying tools of the type to which this invention relates are fluid operated and are for driving fasteners of types such as the ones having a pin and a collar which is cold-swaged tightly into locking grooves in the pin. Each tool, therefore, includes an anvil enga geable with the collar and a multiple jaw assembly engageable with pulling grooves on the pin. Either the anvil, the jaw assembly, or both parts, are moved so as to provide for a -relative movement of the parts in opposite directions. The structure for accomplishing this relative movement includes a cylinder formed in the gun and a piston mounted in the cylinder for reciprocal movement. On movement of the piston in one direction, the tool anvil and jaw assembly are moved relative to each vother to provide :for driving of the fastener. The piston is then moved in an opposite direction to return the anvil and the jaw assembly to relative Apositions in which the tool is set for another driving operation.

In the tools now in use commercially, the structure for reversing the direction of travel of the piston consists of a valve mechanism assembled in the driving tool. Such a tool is, therefore7 complex, heavy, and subject to mechanical mis-adjustments. Furthermore, since the operators of such tools are usually not capable of correctly adjusting the tools, additional difficulty is caused by unnecessary and improper operator adjustments.

An object of this invention, therefore, is to provide a power unit and driving tool assembly in which the necessary valve mechanism for reversing the direction of travel of the tool piston is incorporated in a unit which is remote from the tool so that the tool is of a simplified construction and is of light weight.

A further object of this invention is to provide an improved fastener applying tool which is of a simplied construction.

Another object of this invention is to provide a power unit which includes an auxiliary uid chamber that is expansible for receiving additional fluid when the fluid pressure in the tool is above a predetermined pressure required for tool operation, with the auxiliary fluid chamber being also contractible to supply make-up fluid to these same passages when leakage has reduced the Volume of fluid therein.

A further object of this invention is to provide a power unit for a fastener driving tool which is simple in construction, economical to manufacture, `and efcient in operation in providing the necessary uid pressures for operating the tool.

Further objects, features and advantages of this invention will become apparent from a consideration of the following description, the appended claims and the accompanying drawing in which:

FIGURE l is a vertical sectional view of the power unit of this invention, looking substantially along the line 1-1 in FIG. 2;

FIG. 2 is a top view of the power unit of this invention, with parts of the handle therefor broken away;

FIG. 3 is a horizontal sectional View looking substantially along the line 3 3 in FIG. 1;

FIGS. 4 and 5 are fragmentary enlarged sectional views looking along the lines 4-4 and 5--5 in FIG. 2;

FIG. 6 is a horizontal sectional view looking along the line 6-6 in FIG. l;

FIG. 7 is a fragmentary side elevational view of a lower portion of the power unit of this invention;

FIG. 8 is a horizontal sectional view looking substantially along the line 8 8 in FIG. l;

FIGS. 9 and l0 are enlarged fragmentary sectional views looking along the lines 9-9 and 11i-1G in FIG. 2;

FIG. 11 is a wiring diagram showing the circuit for the switches and the valve operating solenoid in the power unit of this invention;

FIG. 12 is a side elevational view of a driving tool adapted to be used with the power unit shown in FIG. 1 with some parts broken away and other parts shown in section for the purpose of clarity;

FIG. 13 is a fragmentary sectional View looking along the line 13-13 in FIG. 12;

FIG. 14 is a side elevational view of another driving tool adapted to be used with the power unit shown in FIG. 1, with some parts broken away and other parts shown in section for the purpose of clarity;

FIG. 15 is a fragmentary sectional view as seen along the line 15-15 in FIG. 14.

FIG. 16 is a fragmentary plan View of the barrel portion of the tool shown in FIG. 14, with some parts broken away for the purpose of clarity; and

FIG. 17 is a fragmentary elevational view of a portion of the tool shown in FIG. 14.

With reference to the drawing, the power unit of this invention, indicated generally at 10, is illustrated in FIG. l as including a base 12 which carries an upwardly extending cylinder member 14. An upright reservoir member 16 is mounted on the upper end of the cylinder member 14. A. cap or cover Ztl, for the reservoir 16, also acts to secure `a horizontal exible diaphragm 18 lto the reservoir 16. Upright connecting bolts 2.2` extend between the base 12 and the cover 20t for holding the cylinder member 14, the reservoir member 1.6 and the cover member Ztl in positions extending upwardly on the base 12. A tubular handle member 214, of circular shape, is secured by

bolts

2,6 to the cover member 2i)` which has an upwardly extending bearing portion 26a which slidably supports a tubular stem 23 secured vat its lower end to a central portion of the diaphragm 18. At its upper end the stem 211i carries a collar 27 having a depending annular flange 29 which has a radius equal to the distance 'a release button 31 for a safety switch unit 215 is spaced from the stem axis. The button 31 is mounted on a housing 33 which also supports a re-set button 3S for the unit 25 which is circuit-connected in a manner to be hereinafter described.

The hollow base 12 functions as a housing for a valve assembly 311 (FIG. 8) which includes a solenoid 32a mounted in a casing 32 and a valve body 34 actuated in response to energization of the solenoid 32a. A stationary valve passage member '36 connected to a supply line 3S for air under pressure is` formed with substantially parallel air passages 41B, 42, 44, 416 and 4S for a purpose to appear presently.

Mounted for up and down reciprocation in the cylinder 14 is a hollow piston member 50 which has a tubular central portion 52 arranged for up and down sliding movement on an upright piston member 54 secured to and extending downwardly from the lower wall 56 for the reservoir member 16. The lower wall 51 for the piston Si) closes the lower end of the tubular portion 52 so as to form a iluid chamber 53 in the tubular portion between the lower end of the piston 54 and the lower wall 51 of the piston Stl.

The valve body 34 is movable between a first spr-ingurged position `and a second solenoid-moved position when the solenoid 32a is energized. The passage 40 in the valve passage member 36 rconnects the valve body 34 with the air inlet line 38 in both the positions of the body 34. In the spring-urged position of the body 34, the passage 44 communicates, by way of the body 34, with the air inlet passage 49 and, through a passage 53 (FIG. 4) rin the walls of the cylinder member 14 and the reservoir 'member 16, with the interior of the cylinder member 14 on the top side of the piston Sii. ln this position of the body 34, the passage 46, which is connected to an outlet passage 47 in the cylinder wall, communicates with the cylinder 14 below the piston 50, and the passages 42 and 4S are closed at the body 34. The piston 50` is thus moved downwardly in the cylinder 14. In the solenoid actuated position of the body 34 the passages 44 and 46 are closed, the passage 42 communicates with the passage 58 and with `anexhaust passage y49 in the cylinder wall, and the passage 48 is connected Ithrough the body 34 with the supply passage 40 for supplying air under pressure to the cylinder 14 below the piston 50, so that the piston 51B is moved upwardly in the cylinder 14.

The chamber S3 and communicating fluid passages are filled with a hydraulic huid so that when air is supplied to the cylinder 14 below the piston bottom wall 51 and the piston member 5@ moves upwardly in the cylinder 14, fluid is forced out of the chamber 53 through an upright passage 60 in the fixed piston 54, through a horizontal passage 6-2 lin the reservoir `lower wall 56 to a flexible high pressure conduit 64 on the reservoir member 16. The member 64 communicates with a driving tool such as those .shown in FGS. l2-l5, inclusive, to be operated by the power unit 10.

When the circuit for the solenoid 32a is opened so that air under pressure is supplied to the cylinder member 14 on the top side of the piston Si); the piston member is forced downwardly in the cylinder 14 so that fluid in an annular chamber 66 which surrounds the piston member 50 is forced out of the chamber 66 through a horizontal passage 68 in the cylinder wall into a liexible conduit member 70 which also communicates` with the driving tool. As shown in FIG. 1, the piston member 50 has an upper portion 72 and a lower portion 74 of a reduced diameter relative to the portion 72 with a horizontal shoulder 76 being formed at the juncture of the portions. The cylinder 14 has corresponding reduced and enlarged bore sections 78 and S1 for slidably supporting the piston sections 72 and 74. On downward movement of the piston member 50, the upper enlarged portion '72 thereof acts to displace fluid in the annular chamber 66 tofraise the pressure of the fluid and force it out of the chamber 66 and the conduit member 701.

It can thus be seen that in the solenoid-moved position of the vaive body 34, air under pressure is supplied to the lbottom side of the piston 50 and exhausted from the top side so as to force fluid under pressure into the conduit member 64. By virtue of the relative areas of the lower ends of the piston members 50i and 54, fluid is delivered to the conduit 64 at a substantial pressure. When the valve body 34 is returned to its spring-urged position, air under pressure is supplied to the top side of the piston 50 and exhausted from the bottom side. The piston 50 is thus moved downwardly to force iiuid under pressure through the conduit member 70. This pressure in the conduit member 70 is reduced relative to the pressure in the conduit 64.

The higher pressure Huid in the conduit member 64 is used to move the piston in the driving tool in a direction to drive the fastener, as will be described in detail hereinafter. Fluid from the conduit member 70A returns the tool piston to a set position for the next driving operation.

A pair of driving

tools

150 and 200 are shown in FIGS. 12 and 14, respectively, that are adapted to be used with the power unit 10. Since the tools 150` and 200 are conventional in the sense that they include the usual anvil, collet, and mechanical structure for moving these parts relative to each other, only the hydraulic mechanism and the control switches will be described in detail hereinafter. The tool includes a body 152 having a cylinder portion 154 in which a piston 156 is slidably mounted.

A pair of fluid passages 158 and 1611` in the valve body 152 communicate with the cylinder 154 on what for convenience of description will be referred to as the bottom side `162 and top side 164, respectively, of the piston 156. The flexible conduits 64 and 7@ are connected to the body 152 so that they communicate with the passages 15S and 160, respectively. As a result, when the piston St is moved upwardly to force uid under pressure out of the unit 111 through the conduit member `64, this liuid is delivered to the cylinder 154 so as to exert an upward force on the piston 156 and in turn operate the tool 151? to drive the fastener to which the tool is applied.

A tubular member 166 carried by the piston 156 moves upwardly along with the piston. The tubular member 166 carries a radially inwardly projecting pin 170 which rides in a groove 174 formed in a switch actuating rod 172 that is slidably supported in the tubular member 166. When the piston 156 has traveled upwardly a distance necessary to move the pin 170 to the upper end of the groove 174, further upward movement of the piston causes upward movement of the rod 172l to open a switch 136 connected to the lower end of the rod. As shown in FIG. ll, the switch 136 is connected in a circuit indicated generally at 130 which includes the usual leads L1 and L2, the solenoid 32a, the reservoir safety switch 25, and a switch 134 operated by a trigger `180 on the tool 150.

In a fastener driving operation, the operator actuates the trigger 18d to close the trigger switch 134 and energize the solenoid 32a which in turn acts to move the valve body 34 as previously described so that the unit 10 operates to move the tool piston 156 in a driving direction. At the completion of the driving stroke of the piston 156, the switch 136 is opened by the actuating rod 172 so that the solenoid 32a is automatically de-energized. The valve body 34 returns and the power unit y10 operates to force iiuid under pressure through the conduit 70 and piston 50 to return the tool piston '156 to a position in readiness for a subsequent gun operation. The trigger is of course released by the operator when the switch 136 is opened since it is apparent that the movement of the tool 150 to drive a fastener has been completed. Return of the piston 156 to a position against the cylinder bottom wall 182 moves the pin 170 against the rod 172 at the lower end of the groove 174 and moves the rod 172 downwardly to again close the switch 136.

The driving tool 20? likewise includes a body 202 having a cylinder portion 2114 in which a piston 206 is mounted for reciprocal movement. Passages 208 and 21u in the tool handle 2119 communicate through

other passages

211 and 213, respectively, with opposite ends of the cylinder 204 and are connected to the conduits 64 and 7 il, respectively.

The piston 206 has a forwardly projecting extension 240 arranged concentrically within an annular seal 242 mounted in the body 292. An annular slideway 244 for the tubular inner end portion 24o of a pintail ejecting plunger 248 is formed in the extension 240` by inserting a smaller hollow cylinder 251Bv in an elongated opening in the extension 246/. The plunger 248 is part of a nose attachment, indicated generally at 252, removably mounted on the tool 21N? for setting fasteners and rivets of the type having a pull pin. The nose attachment 252 includes a barrel 254 having a radially extending ear 256 positioned in a groove 25S in the body 202.

A spring 260 in the cylinder 25u engages the plunger 248 at the forward end of the tubular portion 246 and urges the plunger 248 in a direction outwardly of the tool to a stop position in which a shoulder 262 on the plunger engages a shoulder 264 on a tubular slide support 256 for the plunger 248. The slide support 266 is positioned within an actuating sleeve 268 having a tapered annular surface 270 at its forward or outer end which engages a similar surface 272 on an expandable and contractible annular jaw assembly 274. A ring 278 support-s the outer end of the slide support 266 and engages the inner end of the jaw assembly 274. A spring 280 extends between the ring 278 and annular ears 282 on the inner end of the slide support 266 and urges the jaw assembly 274 axially outwardly of the sleeve 268 to maintain the inclined surfaces 270 and 272 in engagement. A retainer ring 284 in a groove 286 formed in the inner surface of the `sleeve 268 maintains the jaw assembly 274, the ring 278 and its associated spring '280, and the slide support 266 in an assembled position within the sleeve 268 so that all of these parts can be handled as a unit when the nose assembly 252 is detached from the tool body 202.

The barrel 254 has a detachable anvil 290' at its forward or outer end which is replaceable when it becomes worn or damaged. The anvil 290 has a longitudinally extending flange 292 at its rear end which ts about the barrel 254 and a shoulder 294 which abuts the outer end of the barrel 254. The ange 292 is radially offset from the anvil 290 so as to form a shoulder 296 which extends radially outwardly from the outer surface of the anvil 290 for a purpose to appear presently. Longitudinally extending ears 298 on the outer end of the barrel 254 fit in slots 300 in the anvil 290 in `a position of the barrel within the anvil flange 292. The ears 300 terminate at their outer ends in radially outwardly extending projections 302. To retain the anvil '290 on the barrel 254, a removable retaining ring 304 is extended about the anvil 290 between the shoulder 296 on the anvil and the projections 302 on the barrel. To remove the anvil 290 for replacement, it is only necessary to remove the ring 302 and withdraw the anvil from the barrel.

In the assembly of the nose attachment 252 and the tool -body 202, the inner end of the actuating sleeve 266 is threaded onto an outer end portion 306 of the piston extension 240. The barrel 254 is extended into the tool body 202 to a position against the outer end of the seal 242 with the ear 256 on the barrel located in a slot 308 in the lower side of the barrel 254. On rotation of the barrel, the retaining ear 256 slides into the groove 258, which terminates at its ends at the slot 308, and prevents the barrel from being removed from the body 202. A spring-pressed pin 310 has an enlarged head 312 which engages a pin 314 extending across the slot 308 at a position radially outwardly of the ear 256 to position the head 312 at the ends of the groove 253 and in the path of the ear 256 so that the ear cannot be accidentally positioned in the slot 308 to permit removal of the barrel 254. In order to remove the nose attachment 252, it is necessary to rst manually depress the pin 310 to a position in which the head 312 is out of the path of movement of the ear 256.

v In the operation of the tool 200, when fluid under pressure is delivered through the conduit 64 to the passage 208, the piston 206 is moved rearwardly toward a cylinder end Wall 212 which carries a pin 214 projected toward a ball member 216 carried on the piston 206. A spring 218 urges the ball member 216 to a seated position at one end of an axial uid passage 220 in the piston 206. The passage 220 communicates with the passage 208 through inclined piston passages 222 when the ball 216 is moved ofi` its seat against the pressure of the spring 218. As -a result, when the piston 206 has been moved to a position in which the pin 214 unseats the ball 216, the driving operation of the tool is completed because fluid from the conduit member 208 is merely dumped through the

piston passages

220 and 222 into the passage 210 for return to the-power unit 10. The operator then releases the tool trigger 230, which Vactuates a switch like the switch 134 connected in series with the solenoid 32a, so that the switch is opened and the solenoid 32a is de-energized and the power unit 10 is operated to force uid under pressure through the con- 6 duit '70. In the event the full stroke of the piston 206 is not required to set the fastener, the trigger 230 is of course released as soon as the fastener is set.

Prior to actuation of the trigger 230, the nose attachment 252 is assembled with a fastener to be applied in the usual manner so that the fastener stem or pin extends axially through the contractible jaw assembly 274 and the ejector plunger 248 is forced inwardly to compress the spring 260. The sleeve 268 and the jaw assembly 274 cooperate in the manner described in Patent No. 2,114,493 to effect first a gripping and then a pulling of the fastener pin `as the piston 206 travels toward the cylinder wall 212. The reaction to the pulling force exerted on the fastener pin is applied through the anvil 290 to the fastener collar or sleeve. When the pin is fractured, the plunger '248 ejects the pintail and the piston 206 moves the jaw assembly 274 and the sleeve 268 to positions in readiness for the next fastener setting operation. A spacer ring 320 on the outer end of the sleeve 26S prevents the jaw assembly 274 from being contracted on the plunger 24S.

In the tool 200, the piston actuated switch 136 required in the tool 150 is dispensed with and the tool 200 utilizes instead the ball valve 216 in the piston 206.

The chamber (FIG. l) formed in the reservoir member 16 between the diaphragm 18 and the bottom wall 56 is iilled with uid. A chamber 32 formed between the cover 20 and the top side of the diaphragm 18 communicates through a horizontal passage 84 in the cover member 20 with an upright passage 86 extended through the walls of the cylinder member 14 and the reservoir member 16 and communicating at its lower end with the air inlet line 38. Consequently, the diaphragm 10 is subjected to a relatively constant air pressure which provides for 'a predetermined pressure of the diaphragm 18 on the iluid in the chamber 80 so as to likewise maintain this fluid at a predetermined constant pressure.

The chamber 80 communicates with the horizontal passage 62 in the reservoir member 16 through a pair of upright passages 83 and 90 and a horizontal passage 89 in an enlarged outer portion 92 of the reservoir lower wall 56. The passage 39 is aligned with an enlarged horizontal cavity in the reservoir in which a check valve unit 94 of conventional construction is disposed. The unit 94 includes a valve body 98 which is normally held against a seat 10S in the passage 09. When the pressure in the passage is above a predetermined limit the body 90 moves inwardly to admit iluid from the passage 89 to the passage 88 and thence into the chamber S0. This flow continues until the pressure in the passage 89 has been reduced to a lower limit.

It is seen, therefore, that in the event uid in the passage 90, which in turn communicates with fluid in the chamber 53, is raised above a predetermined pressure, the one-way check valve unit 94 acts to provide for a flow of fluid into the chamber 80 which expands to accommodate this extra uid and relieves the pressure in the charnber 53 and communicating Huid passages.

Conversely, in the event the total fluid volume in the chamber 53 and the communicating fluid passages which deliver high pressure fluid to the tool piston is reduced, the pressure of this fluid on a second check valve unit 112 (FIG. l0) mounted on the reservoir member 16 is reduced when the piston 50 is in the position shown in FIG. l. The pressure of the fluid in the chamber 80 which is substantially constant acts on a valve body for the oneway check valve 112 to move the body 110 inwardly when the pressure is reduced in the chamber 53 to provide for a ow of fluid through an upright passage 111 and a horizontal passage 109 in the reservoir lower wall 56 to an upright passage 113 in the fixed piston 54. The passage 113 communicates at its lower end with the chamber 53. The chamber 80 and the check valve unit 112 thus act to continually provide make-up fluid to the chamber 53 to provide for a volume make-up and for a minimum pres- 7 sure therein for operating the driving tool 15) or Edil.

A similar pair of check Valve units 114 and 116 (FlGS. and 9) are installed in the reservoir wall portion 92 and communicate through passages 115 and 117, respectively, with the chamber 66 to provide for a pressure relief and a volume make-up, respectively, for the annular chamber 66. 'I'he chamber t) thus constitutes a fluid source for maintaining a constant volume of operating fluid in the power -unit and the

tool

150 or 200 connected thereto. The chamber dll also acts to accommodate extra Huid in the event the pressure in either of the chambers 53 or 66 becomes excessive. The

check valve units

94, and 114 are adjustable to determine the pressures at which the valve units will open to provide the desired pressure relief, and the

valve units

112 and 116 are likewise adjustable to determine the lower pressure limits in the chambers 53 and 66.

As fluid is moved out ofthe chamber 80, the diaphragm moves toward the reservoir bottom wall 56. The stem 23 and the collar flange 29 are correspondingly moved toward the cover until the ilange 29 engages the switch release button 31 and opens the switch 25. The chamber 80 must then be re-lled and the switch reset with the button 35 before the power unit 10 can be operated.

`From the above description it can be seen that when the power unit 1t) is used, the fastener applying tool, such as one of the tools illustrated, is of a simplified construction without bulky and heavy valve mechanisms. Furthermore, the unit 10 provides for a continued supply of the necessary high pressure lluid to the driving tool while minimizing the danger of uid leakage.

It will be understood that the specific construction of the improved power unit which is herein disclosed and described is presented for purposes of explanation and illustration and is not intended to indicate limits of the invention, the scope of which is delined by the following claims.

What is claimed is:

1. In a fastener applying mechanism which includes a tool having a cylinder portion and a piston mounted in the cylinder portion for movement in one direction toward one position to operate the tool and in an opposite direction to an opposite position for the next fastener applying operation, and a remote power unit for supplying fluid under pressure to said cylinder portion for moving the piston in said opposite directions, valve means on said power unit movable between a rst position in which fluid is supplied from the power unit to said cylinder portion for moving the piston in said one direction and a second position in which fluid is supplied to said cylinder portion for moving the piston in said opposite direction, solenoid means for controlling the position of said valve means, and manually operable trigger switch means on said tool electrically connected with said solenoid means for selectively controlling the actuation of said solenoid means, and means disposed on the tool and operatively associated with the piston independently of said trigger switch means for relieving the fluid pressure from one side of the piston responsively to the piston reaching one of said one position and said opposite position.

2. In a fastener applying mechanism which includes a tool having a cylinder portion and a piston mounted in the `cylinder portion for movement in one direction to operate the tool and in an opposite direction to a set position for the next fastener applying operation, and a rcrnote power unit for supplying iluid under pressure to said cylinder portion for moving the piston in said opposite directions, valve means on said power unit movable between a rst position in which fluid is supplied from the power unit to said cylinder portion for moving the piston in said one direction and a second position in which fluid is supplied to said cylinder portion for moving the piston in said .opposite direction, solenoid means for controlling the position of said valve means, manually operable trigger switch means on said tool electrically connected with said solenoid means for selectively controlling the actuation of said solenoid means, normally closed d switch means on said tool connected to said piston for movement to an open position in response to completed movement of said piston in said one direction and electrically connected to said solenoid means and to said trigger switch means for controlling the actuation of said solenoid means independently of said trigger switch means.

3. In a fastener applying mechanism which includes a tool having a cylinder portion and a piston mounted in the cylinder portion for movement in one direction to operate the tool and in an opposite direction to a set position for the next fastener applying operation, and a remote power unit for supplying lluid under pressure to said cylinder portion for moving the piston in said opposite directions, valve means on said power unit movable between a first position in which fluid is supplied from the power unit to said cylinder portion for moving the piston in said one direction and a second position in which tluid is supplied to said cylinder portion for moving the piston in said opposite direction, solenoid means for controlling the position of said valve means, manually operable trigger switch means on said tool electrically connected with said solenoid means for selectively controlling the actuation of said solenoid means, and normally closed valve means responsively to the said tool movable to an open position on completion of said movement of the piston in said one direction for fluid communicating opposite sides of said piston.

4. A fastener applying mechanism comprising a tool having a cylinder portion and a piston mounted for reciprocal movement in said cylinder portion between limit positions adjacent opposite ends of said cylinder portion, switch means mounted on said tool for controlling the actuation of the movement of said piston to said limit positions, said switch means including trigger switch means selectively operable for `controlling the actuation of said piston for movement to one of said limit positions, said switch means further including control switch means mounted on said tool for controlling actuation of said movement of said piston to the other of said limit positions, and means responsive in operation to movement of said piston to said one of said limit positions for substantially instantaneously actuating said switch means.

5. A fastener applying mechanism comprising a tool having a cylinder portion and a piston mounted for reciprocal movement in said cylinder portion between limit positions adjacent opposite ends of said cylinder portion, switch means mounted on said tool for controlling the actuation of the movement of said piston to said limit positions, said switch means including trigger switch means selectively operable for controlling the actuation of said piston for movement to one of said limit positions, said switch means further including control switch means mounted on said tool for controlling actuation of said movement of said piston to the other of said limit positions, and lost motion means connecting said piston and said switch means so that the switch means is substantially instantaneously actuated when said piston moves to said one of said limit positions.

6. A fastener applying mechanism comprising a tool having a cylinder portion and a piston mounted for reciprocal movement in said cylinder portion between limit positions adjacent opposite ends of said cylinder portion, switch means mounted on said tool for controlling the actuation of the movement of said piston, and valve means on said piston movable to an open position in response f to movement of said piston to one of said limit positions for lluid communicating opposite sides of the piston.

7. A fastener applying mechanism comprising a tool having a cylinder portion, a piston member mounted for reciprocal movement in said cylinder portion, and duid conduits adapted to Ibe supplied with fluid under pressure for delivering the liuid to said Kcylinder portion on one side of said piston member `for moving said piston member in one direction to operate said tool to apply a fastener and on the opposite side of said piston member for moving said piston member in a return direction, normally closed valve means in said piston member operable in an open position to iiuid communicate the portions of said cylinder portion on opposite sides of said piston, and means on said tool for Opening said valve means when said piston member has moved a predetermined distance in said one direction.

8. A fastener applying mechanism comprising a tool having a cylinder portion, a piston member mounted for reciprocal movement in said cylinder portion, and tluid conduits adapted to be supplied with fluid under pressure for delivering said iluid to the cylinder portion on one side of said piston member `for moving said piston member in one direction to operate said tool to apply a fastener and on said opposite side of said piston member for moving the piston member in a return direction, normally closed valve means in said piston member operable in an open position to fluid communicate the portions of said cylinder portion on opposite sides of said piston, said valve means including a passage formed in said piston member, a ball member mounted on said piston member for movement to a seated position closing said passage, means resiliently urging said ball member to said seated position, and means on said tool engageable with said ball member for moving said ball member away from said seated position against the pressure of said urging means when said piston member has moved a predetermined distance in said one direction.

9. A fastener applying mechanism -operable with a source of fluid under pressure comprising a tool having a cylinder portion, a piston member mounted for reciprocal movement in said cylinder portion, and uid conduits adapted to be supplied with tiuid under pressure for delivering the Huid to said cylinder portion on lone side of said piston member for moving said piston member in one direction to operate said tool to apply a `fastener and on the opposite side of said piston member for moving said piston member in a return direction, normally closed valve means on said piston member operable in an open position to fluid communicate the portions of said cylinder portion on opposite sides of said piston, means on said tool for opening said valve means when said piston member has moved a predetermined distance in said one direction, and means including `a manually operable switch on said tool for providing a supply of fluid under pressure from the source to said cylinder portion on lone side of said piston member when said switch is in a iclosed position and for providing a `supply of uid under pressure from the source to the opposite side of said piston member when said switch is in an open position.

10. A fastener applying mechanism comprising a tool having a cylinder portion and a piston mounted for reciprocal movement in said cylinder portion between limit positions adjacent opposite ends of said cylinder portion, switch means for controlling the actuation of the movement of said piston to said limit positions, said switch means including trigger switch means selectively operable to control actuation of the movement of said piston to one of said limit positions, said switch means further including control switch means mounted Von `said tool for, upon actuation, deactuating said trigger switch means and for controlling the actuation of the movement of said piston to the other of said limit positions, and means responsive in operation to movement of said piston to said one of said limit positions for substantially instantaneously actuating said control switch means.

l1. A fastener applying mechanism comprising a tool having a cylinder portion and a piston mounted for reciprocal movement in said cylinder portion between limit positions adjacent opposite ends of said cylinder portion, switch means for controlling the actuation of the movement of said piston to said limit positions, said switch means including trigger switch means selectively actuable to control, upon actuation, the actuation of the movement of said piston to one of said limit posi-tions and, upon deactuation, the movement of said piston to the other of said limit positions, said switch means further including control switch means mounted on said tool for, upon actuation, deactuating said trigger switch means and for controlling the actuation of the movement of said piston to the other of said limit positions, and means responsive in operation to movement of said piston to said one of said limit positions for substantially instantaneously actuating said control switch means.

12. The mechanism of claim 11 further including means responsive in operation to movement of said piston to said other of said limit positions tor deactua-ting said control switch means.

13. A fastener applying mechanism comprising a tool having a cylinder portion and a piston mounted for reciprocal movement in said cylinder portion between limit positions adjacent opposite ends of said cylinder portion, switch means for `controlling the actuation of the movement of said pi-ston to said limit positions, said switch means including a normally opened trigger switch selectively operable to control, upon being closed, the actuation of the movement of said piston to one of said limit positions and upon being opened, the movement of said piston to the other of said limit positions, said switch means further including a normally closed control switch mounted on said tool for deactuating said trigger switch means upon being opened and for controlling the actuation of the movement of said piston to the other of said limit positions, and mean-s responsive in operation to movement of said piston to said one oti said limit positions for substantially instantaneously opening said control switch and responsive in operation to movement of said piston to said other of said limit positions for substantially instantaneously closing said control switch.

References Cited in the file of this patent UNITED STATES PATENTS 394,383 Miller Dec. 11, 1888 477,822 Potter June 28, 1892 523,925 Bierce et al. July 31, 1894 774,266 McMullen Nov. 8, 1904 1,038,524 Bossert Sept. 17, 1912 1,970,999 Ferris et al. Aug. 21, 1934 2,308,712 Peterson et al. Jan. 19, 1943 2,359,949 Van Der Weri Oct. 10, 1944 2,365,536 Fischer et al. Dec. 19, 1944 2,368,659 Heineck et al. lFeb. 6, 1945 2,389,654 Van Der Wer Nov. 27, 1945 2,493,377 Zeilman Jan. 3, 1950 2,511,541 Purcell June 13, 1950 2,525,626 Stouter et al. Oct. 10, 1950 2,526,956 Kugler Oct. 24, 1950 2,539,720 Bender Jan. 30, 1951 2,677,239 Parker May 4, 1954 2,691,962 Johnson Oct. 19, 4 2,713,439 Dumas July 19, 1 955 2,851,014 Healy Sept. 9, 1958 Patent No 3,052,099

UNITED STATES vPATENT OFFICE CERTIFICATE OF CORRECTION September 4, 1962 George J., Van Hecke It is hereby certified that err-or appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

line line read (SEAL) Attest:

Column 8, line 24', for "responsvely to the" read on 25, for nom" read responsively to the column 9, l1, for "said" read the same line Il, for "the" Vsigned and sealed this 27th day of August 1963.

DAVID L. LADD ERNEST W SWIDER Attesting Officer Commissioner of Patents