US2123563A - Power hammer - Google Patents

Power hammer Download PDF

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Publication number
US2123563A
US2123563A US95892A US9589236A US2123563A US 2123563 A US2123563 A US 2123563A US 95892 A US95892 A US 95892A US 9589236 A US9589236 A US 9589236A US 2123563 A US2123563 A US 2123563A
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Prior art keywords
piston
rod
handle
cylinder
fuel
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Expired - Lifetime
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US95892A
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Albert F Cresien
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Individual
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B25HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
    • B25DPERCUSSIVE TOOLS
    • B25D9/00Portable percussive tools with fluid-pressure drive, i.e. driven directly by fluids, e.g. having several percussive tool bits operated simultaneously
    • B25D9/06Means for driving the impulse member
    • B25D9/10Means for driving the impulse member comprising a built-in internal-combustion engine

Definitions

  • This invention relates to power hammers and the objects of the invention are to provide a gasoline driven hammer which may be used for drill ing, demolition work or other purposes, to pro- Vide a hammer which is portable, and also to provide a hammer having safety features associated therewith to the end that the hammer will cease operating when pressure is released on the handle.
  • the invention consists in the provision of a gasoline driven, air cooled, two cycle hammer which will be found to possess numerous and advantageous features over the types of power hammers now generally employed.
  • Figure l is an elevational view of the improved power hammer.
  • Figure 2 is a longitudinal sectional View through the hammer.
  • Figure 3 is a horizontal sectional view through a latch mechanism forming part of the invention.
  • Figure 4 is a fragmentary longitudinal sec tional View through a rod assembly forming part of the invention.
  • Figure 5 is a fragmentary detail sectional view showing the manner of connecting the handle with a casting forming part of the invention.
  • Figure 6 is an enlarged detail sectional view through a carburetor inlet assembly forming part of the invention.
  • Figure 7 is a top plan view of an air breather
  • Figure 8 is a side elevational view of the air breather with certain parts broken away and shown in section.
  • the improved power hammer comprises a substantially hollow handle 5, which includes a hollow cross member 6 having depend- 45 ing therefrom parallel extensions 1.
  • the handle 5 forms a container for fuel, in the present instance gasolene and to that end at one end of the grip 5, the handle 5 is provided with a filling neck It).
  • the invention comprises a casting 9 that has extended from diametrically opposite sides thereof lugs 8, which as best shown in Figure 5 are provided with a socket which receives the tapered solid ends of the handle extensions 55 l. Screws or similar fastening elements 4 serve to positively secure said ends of the handle extensions within the sockets of the lugs 8.
  • the block 9 has formed integrally therewith a cylinder i5 in which operates a piston M.
  • the piston i4 is guided in its movements through the medium of guide rods ll suitably anchored within a bored portion of the block 9 as shown in Figure 2. Also within the lower end of the bored portion of the block 9 is an impact assembly I 3 for operating the tool l2 which is connected with the impact assembly it through the medium of a chuck or other suitable coupling H.
  • the bored portion of the block 9 below the piston M constitutes a carburetor having an inlet 32.
  • a casting Suitably associated with the inlet 32 of the block 9 is a casting which includes an air intake valve 35 fitted within the intake 32 and con' trolled by a valve disk 33 having a stem operating in a suitable guide structure 34 and with which is associated a spring 36 that normally retains the valve 33 seated at the inner end of the intake 3!.
  • the guide 34 is provided with openings 35 through which air from the atmosphere enters the neck 3
  • the lower ends of the handle extension 1 are provided with ports 2
  • a passage 2lb Suitably cored within the blocks 9 is a passage 2lb that connects the passages 21a with a passage 22 (see Figure 6) that opens into a fuel reservoir 23.
  • the fuel in the reservoir seeks a suitable level, and the level of fuel in the reservoir 23 may be ascertained by looking through a sight window 25 with which the reservoir 23 is suitably equipped.
  • the reservoir 23 is provided with a suitable plug 24.
  • the reservoir 23 is provided with a collector cup 26 and a tube El arranged centrally of the cup 26 and extending through the bottom of the reservoir chamber 23 into an integral valve casing 28.
  • Collector cup 26 and tube 2i are so designed as to prevent vapor lock and also the formation of bubbles that would interrupt the gasoline supply under high vibration.
  • valve 33 being open air from the atmosphere is drawn into the carburetor portion of the block 9 through a breather 54 hereinafter more fully referred to and past the valve 33 to mix with the fuel admitted into the carburetor in the manner just explained.
  • a passage 3 Formed in the block 9 and wall of cylinder I is a passage 3 which at one end opens into the carburetor portion of the block 9 and at its other end opens as at 2 into the cylinder I5 above the piston I4 when the latter is in its lowest position.
  • a plug for the port 2 as indicated by the reference numeral 31 is provided as shown in Figure 2.
  • the breather assembly 54 includes a union 54a that connects the pipe with a nipple 542) that is received within a recess 3Ib provided in the casting assembly of Figure 6 at the side of the guide 34 opposite to the valve 33.
  • Pipe 54 is provided with airports 55 through which the air passes from the atmosphere through the breather, the passages 35, and pass the valve 33, when the latter is in open position to mix with the fuel entering the carburetor portion of the block 9 below the piston I4.
  • the make and break ignitor which may be of any suitable construction and design, and forms no part of the present invention is preferably of the compression responsive type and is therefore under the control of piston l4, and is suitably mounted on a head I9 provided for the cylinder I5.
  • the head I9 is suitably bored to provide a guide for actuator rod 49 that moves vertically through the head I9 and has an inner end adapted to engage the head of the piston I4 for initiating downward movement of the piston as will hereinafter be more fully explained.
  • which at its lower end is provided with a pair of spaced collars between which are pivoted latch dogs 41 between one end of which is a spring 48 that normally urges the free ends of the dogs 41 inwardly towards one another.
  • are normally urged towards one another through the medium of a spring 42 which at one end is anchored within the rod 4
  • the rod 40 is provided at opposite sides thereof with grooves or slots 53 with which the latch element 41 engage when the rod 4
  • is bifurcated to receive an intermediate portion of a bracket 43 the opposite ends of which are suitably secured to a handle member I pivoted at one end to a clamp 45 secured about an end portion of the grip 6 of handle 5.
  • roller 46 which engages the intermediate portion of the bracket 43.
  • handle I is swung upwardly for pulling the rod 4
  • latch members 41 are brought opposite the grooves and under action of spring 48 move inwardly into engagement with the grooves 50 thus locking the rods 40 and 4
  • handle I is then moved downwardly.
  • rod 49 at its inner end engages the piston I4 at the head of the latter and forces said piston downwardly of the block 9 against the action of spring I8.
  • the piston I4 moves downwardly the fuel mixture below the piston is forced through the passage 3 and the port 2 into the cylinder I5 above the piston I4.
  • piston I4 will then move downwardly on its power stroke against the action of spring I8, and this cycle of operation is repeated for the continuous operation of the hammer.
  • the igniting device 20 may be arranged in a suitable battery circuit and for controlling this circuit there is provided a switch consisting of a contact 53 suitably mounted on and insulated from the grip B of handle 5 and a contact 52 suitably mounted on and insulated from the handle I and bracket 43.
  • a switch consisting of a contact 53 suitably mounted on and insulated from the grip B of handle 5 and a contact 52 suitably mounted on and insulated from the handle I and bracket 43.
  • handle I is depressed sufficiently to maintain contacts 52 and 53 engaged.
  • handle I will move slightly upwardly to separate the contacts 52 and 53.
  • a device of the character described the combination with a cylinder having a floating piston reciprocable therein, an impact assembly in the lower end of said cylinder, and a spring acting upon said piston and in opposition to the movement thereof toward said impact assembly; means for initiating movement of the piston against the action of the spring and including a head for said cylinder having a bore therethrough, an actuator rod slidable through the bore in said head and having an inner end adapted to engage the piston for moving the latter downwardly, a tubular rod slidably mounted on said actuator rod, and interengaging means on the actuator rod and on said tubular rod for releasably connecting said rods together when the tubular rod is moved in one direction relative to the actuator rod whereby upon reverse movement of said tubular rod said actuator rod is caused to move inwardly of the cylinder to engage the piston for moving the latter toward said impact assembly in opposition to said spring, and means on the upper end of the cylinder for releasing the rod at the completion of the movement of the piston toward said impact assembly, whereby said actuator rod is free

Description

A. F/. CRESIEN July 12, 1938.
POWER HAMMER Filed Aug. 15, 1936 5 Sheets-Sheet 1 Invenlor flibrff'fasz'em,
Jul 12, 1938. A. F. CRESIEN 2,123,563
POWER HAMMER Filed Aug. 15, 1936 3 Sheets-Sheet 2 EIEIZE/M Inventor By Wan/5M i g Attorneys July 12, 1938. A. F. CRESIEN 2,123,563
POWER HAMMER Filed Aug. 15, 1936 s'sheets-sheet 5 ZZWw/EM. 5
A ito rneys Patented July 12, 1938 UNITED STATES PATENT OFFICE 3 Claims.
This invention relates to power hammers and the objects of the invention are to provide a gasoline driven hammer which may be used for drill ing, demolition work or other purposes, to pro- Vide a hammer which is portable, and also to provide a hammer having safety features associated therewith to the end that the hammer will cease operating when pressure is released on the handle.
Briefly, the invention consists in the provision of a gasoline driven, air cooled, two cycle hammer which will be found to possess numerous and advantageous features over the types of power hammers now generally employed.
The invention together with its objects and advantages will be best understood from a study of the following description taken in connection with the accompanying drawings wherein:
Figure l is an elevational view of the improved power hammer.
Figure 2 is a longitudinal sectional View through the hammer.
Figure 3 is a horizontal sectional view through a latch mechanism forming part of the invention.
Figure 4 is a fragmentary longitudinal sec tional View through a rod assembly forming part of the invention.
Figure 5 is a fragmentary detail sectional view showing the manner of connecting the handle with a casting forming part of the invention.
Figure 6 is an enlarged detail sectional view through a carburetor inlet assembly forming part of the invention.
Figure 7 is a top plan view of an air breather, and
Figure 8 is a side elevational view of the air breather with certain parts broken away and shown in section.
Referring to the drawings by reference numerals it will be seen that in the preferred embodiment thereof the improved power hammer comprises a substantially hollow handle 5, which includes a hollow cross member 6 having depend- 45 ing therefrom parallel extensions 1. The handle 5 forms a container for fuel, in the present instance gasolene and to that end at one end of the grip 5, the handle 5 is provided with a filling neck It).
Further the invention comprises a casting 9 that has extended from diametrically opposite sides thereof lugs 8, which as best shown in Figure 5 are provided with a socket which receives the tapered solid ends of the handle extensions 55 l. Screws or similar fastening elements 4 serve to positively secure said ends of the handle extensions within the sockets of the lugs 8.
The block 9 has formed integrally therewith a cylinder i5 in which operates a piston M.
The piston i4 is guided in its movements through the medium of guide rods ll suitably anchored within a bored portion of the block 9 as shown in Figure 2. Also within the lower end of the bored portion of the block 9 is an impact assembly I 3 for operating the tool l2 which is connected with the impact assembly it through the medium of a chuck or other suitable coupling H.
The bored portion of the block 9 below the piston M constitutes a carburetor having an inlet 32.
Suitably associated with the inlet 32 of the block 9 is a casting which includes an air intake valve 35 fitted within the intake 32 and con' trolled by a valve disk 33 having a stem operating in a suitable guide structure 34 and with which is associated a spring 36 that normally retains the valve 33 seated at the inner end of the intake 3!. The guide 34 is provided with openings 35 through which air from the atmosphere enters the neck 3| to pass from the neck 3| into the carburetor portion of the block 9 below the piston I4.
The lower ends of the handle extension 1 are provided with ports 2| that register with ports 2la. provided in the lugs 8. Suitably cored within the blocks 9 is a passage 2lb that connects the passages 21a with a passage 22 (see Figure 6) that opens into a fuel reservoir 23.
The fuel in the reservoir seeks a suitable level, and the level of fuel in the reservoir 23 may be ascertained by looking through a sight window 25 with which the reservoir 23 is suitably equipped. In the top thereof the reservoir 23 is provided with a suitable plug 24. At the bottom thereof, the reservoir 23 is provided with a collector cup 26 and a tube El arranged centrally of the cup 26 and extending through the bottom of the reservoir chamber 23 into an integral valve casing 28. Collector cup 26 and tube 2i are so designed as to prevent vapor lock and also the formation of bubbles that would interrupt the gasoline supply under high vibration.
Leading from one end of the valve casing 28 through the peripheral wall of the intake neck 3! is a. fuel passage 30 which is also controlled by the valve 33 as shown in Figure 6.
From the above it will be seen that on each upward stroke of piston 94, fuel from the handle 5 flows through the ports 2|, 21a, Zlb, 22 into the reservoir 23.
From the reservoir 23, fuel passes through the tube 21 into the valve 28, and from the valve 28 through the passage 30 and from the jet 30, the fuel passes into the intake 32 of the carburetor portion of casting of block 9. At the same time, valve 33 being open air from the atmosphere is drawn into the carburetor portion of the block 9 through a breather 54 hereinafter more fully referred to and past the valve 33 to mix with the fuel admitted into the carburetor in the manner just explained.
Formed in the block 9 and wall of cylinder I is a passage 3 which at one end opens into the carburetor portion of the block 9 and at its other end opens as at 2 into the cylinder I5 above the piston I4 when the latter is in its lowest position. A plug for the port 2 as indicated by the reference numeral 31 is provided as shown in Figure 2.
Thus it will be seen that as the piston I4 moves downwardly the fuel mixture below the piston within the block 9 is compressed and forced through the passage 3 and port 2 into the cylinder I5 above the piston I4. On the compression stroke of the piston I4 the fuel admitted into the cylinder I5 will be compressed and at the end of this compression stroke the fuel compressed by the upward movement of the piston will be exploded through the medium of the igniting as sembly 28 which may be of any suitable design. Obviously the force of the exploding gases will act on the piston I4 to move the same downward. Thus the cycle of operation is continuously repeated so that the piston I4 in its reciprocatory action acts on the impact assembly I3 in a manner to operate the tool I2.
The breather assembly 54 includes a union 54a that connects the pipe with a nipple 542) that is received within a recess 3Ib provided in the casting assembly of Figure 6 at the side of the guide 34 opposite to the valve 33. Pipe 54 is provided with airports 55 through which the air passes from the atmosphere through the breather, the passages 35, and pass the valve 33, when the latter is in open position to mix with the fuel entering the carburetor portion of the block 9 below the piston I4.
As shown in Fig. 2 the make and break ignitor which may be of any suitable construction and design, and forms no part of the present invention is preferably of the compression responsive type and is therefore under the control of piston l4, and is suitably mounted on a head I9 provided for the cylinder I5.
The head I9 is suitably bored to provide a guide for actuator rod 49 that moves vertically through the head I9 and has an inner end adapted to engage the head of the piston I4 for initiating downward movement of the piston as will hereinafter be more fully explained.
Slidably associated with the rod is a tubular rod 4| which at its lower end is provided with a pair of spaced collars between which are pivoted latch dogs 41 between one end of which is a spring 48 that normally urges the free ends of the dogs 41 inwardly towards one another.
Rods 40 and 4| are normally urged towards one another through the medium of a spring 42 which at one end is anchored within the rod 4|, and at its opposite end is secured to the upper end of the rod 49 as clearly shown in Figure 4.
Also at its upper end the rod 40 is provided at opposite sides thereof with grooves or slots 53 with which the latch element 41 engage when the rod 4| is moved upwardly relative to the rod 40, as and for a purpose hereinafter more fully explained.
At its upper end the rod 4| is bifurcated to receive an intermediate portion of a bracket 43 the opposite ends of which are suitably secured to a handle member I pivoted at one end to a clamp 45 secured about an end portion of the grip 6 of handle 5.
Also and as clearly shown in Figures 1 and 4, suitably provided in the bifurcated end of the rod 4| is a roller 46 which engages the intermediate portion of the bracket 43.
From the above it will be seen that to initiate operation of the hammer, handle I is swung upwardly for pulling the rod 4| upwardly relative to the rod 40. As the rod 4| moves upwardly, latch members 41 are brought opposite the grooves and under action of spring 48 move inwardly into engagement with the grooves 50 thus locking the rods 40 and 4| together. When a this locking of these rods 49 and 4| is effected, handle I is then moved downwardly. As handle I moves downwardly rod 49 at its inner end engages the piston I4 at the head of the latter and forces said piston downwardly of the block 9 against the action of spring I8. As before mentioned as the piston I4 moves downwardly the fuel mixture below the piston is forced through the passage 3 and the port 2 into the cylinder I5 above the piston I4.
Rising from the cap I9 in the path of the levers 41 is the suitably shaped lug 5|. It will thus be seen that as rods 40 and 4| move downwardly for moving the piston I4 downwardly as and for the purpose just mentioned, the latch members 41 will ultimately engage with the lug 5| spreading these latch members 41 apart and out of engagement with the rod 4|, thus releasing the rod. Upon release of the rod 40, the spring I8 will act on the piston I4 to move the same, forcibly, upwardly to compress the fuel admitted into the cylinder I5 above the piston I4. As piston I4 moves upwardly on its compression stroke sufiicient pressure will be developed for setting in operation the make and break device 20 to ignite the compressed fuel above the piston l4. Ob-
. viously under the force of the explosion, piston I4 will then move downwardly on its power stroke against the action of spring I8, and this cycle of operation is repeated for the continuous operation of the hammer.
It will be understood that the igniting device 20 may be arranged in a suitable battery circuit and for controlling this circuit there is provided a switch consisting of a contact 53 suitably mounted on and insulated from the grip B of handle 5 and a contact 52 suitably mounted on and insulated from the handle I and bracket 43. Thus as the handle I moves downwardly for moving the piston I4 downwardly in the manner above explained, the contact 52 will engage contact 53 thus completing the circuit through the ignition device 20 for firing the charge compressed by the upward movement of the piston I4.
In connection with the above it will be understood that during the desired operation of the hammer, handle I is depressed sufficiently to maintain contacts 52 and 53 engaged. Thus it will be seen that when it is desired to stop the operation of the hammer, pressure is released from the handle I and under influence of the spring contact 52 handle I will move slightly upwardly to separate the contacts 52 and 53.
For scavenging the cylinder I5 the latter is provided with an exhaust port 39 which opens to the atmosphere. Thus it will be seen that as piston l4 moves downwardly in response to the explosive action of the gases, port 39 as well as port 2 will be uncovered. Thus the burnt gases will escape through the port 39 and the fuel mixture from below the piston M will be admitted into the cylinder i5 above the piston M.
For controlling the supply of fuel through the jets 30 into the carburetor chamber of the block 9, there is accommodated within the valve casing 28 a needle valve 29 arranged to control the jet 30 as shown in Figure 6.
Since the operation of the invention was described as the description of the details of the invention progressed, it is thought unnecessary to repeat in detail the operation of the device, and that the same will be clear from the foregoing.
Having thus described the invention what is claimed as new is:
1. In a device of the character described, the combination with a cylinder having a floating piston reciprocable therein, an impact assembly in the lower end of said cylinder, and a spring acting upon said piston and in opposition to the movement thereof toward said impact assembly; means for initiating movement of the piston against the action of the spring and including a head for said cylinder having a bore therethrough, an actuator rod slidable through the bore in said head and having an inner end adapted to engage the piston for moving the latter downwardly, a tubular rod slidably mounted on said actuator rod, and interengaging means on the actuator rod and on said tubular rod for releasably connecting said rods together when the tubular rod is moved in one direction relative to the actuator rod whereby upon reverse movement of said tubular rod said actuator rod is caused to move inwardly of the cylinder to engage the piston for moving the latter toward said impact assembly in opposition to said spring, and means on the upper end of the cylinder for releasing the rod at the completion of the movement of the piston toward said impact assembly, whereby said actuator rod is free to telescope inwardly of the tubular rod incidental to the return movement of the piston.
2. In a device of the character described, the
combination with a cylinder having a piston reciprocating therein; of means for initiating movement of said piston including an actuator rod movable through the upper end of the cylinder and inwardly of the latter to engage the piston to move the latter in one direction, a tubular rod slidable on said actuator rod, said actuator rod being provided adjacent one end thereof with grooves, spring pivoted dogs on said tubular rod engageable with said grooves to releasably secure said rods against relative movement when the tubular rod is moved outwardly of said actuator rod, whereby both of said rods are caused to move inwardly to engage the actuator rod with said piston, and a lug mounted on the upper end of the cylinder in the path of said dogs to release the rods at the completion of the movement of the piston toward said impact assembly, whereby said actuator rod is free to telescope inwardly of the tubular rod upon return movement of the piston.
3. In a device of the character described and in combination with a cylinder having a floating piston reciprocable therein, of means for initiating movement of the piston including a head for said cylinder and having a. bore therethrough, an actuator rod slidable through the bore in said head and having an inner end adapted to engage the piston to move the latter in one direction, a tubular rod slidably mounted on said actuator rod, interengaging means on the actuator rod and said tubular rod for releasably connecting said rods together when the tubular rod is moved in one direction relative to the actuator rod whereby upon reverse movement of said tubular rod said actuator rod is caused to move inwardly of the cylinder to engage said piston for moving the latter in said one direction, a handle member pivotally mounted at the head equipped end of said cylinder, a bracket member secured at its respective opposite ends to said handle and having its intermediate portion spaced from said handle, and roller means on one end of said tubular rod and engaging the intermediate portion of said bracket whereby swinging movement of the handle member is transmitted to said tubular rod.
ALBERT F. CRESIEN.
US95892A 1936-08-13 1936-08-13 Power hammer Expired - Lifetime US2123563A (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2738777A (en) * 1950-02-15 1956-03-20 Wampach Aloyse Nicolas Operating and ignition device for an explosion-driven ramming hammer
US5259463A (en) * 1992-10-02 1993-11-09 Ingersoll-Rand Company Throttle lever system for a percussive, fluid-activated apparatus

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2738777A (en) * 1950-02-15 1956-03-20 Wampach Aloyse Nicolas Operating and ignition device for an explosion-driven ramming hammer
US5259463A (en) * 1992-10-02 1993-11-09 Ingersoll-Rand Company Throttle lever system for a percussive, fluid-activated apparatus
US5385209A (en) * 1992-10-02 1995-01-31 Ingersoll-Rand Company Throttle lever system for a percussive, fluid-activated apparatus

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