US3612452A - Power hammer - Google Patents

Abstract

In a power hammer, and particularly in a mounting structure therefor, the power hammer has a frame carried by levers which in turn are carried by blocks mounted on a floor. The frame carries damping cylinders pistons which act on a shock-absorbing damping medium within the cylinders. A transmission extends between the levers and the pistons to cause the latter to tend to move into the cylinders to provide shock absorption by the damping medium in the cylinders when the ram of the hammer strikes against work carried by an anvil of the hammer. In this way, the frame is situated over and out of engagement with a floor which is protected against injury.

Description

United States Patent Primary Examiner.I. Franklin Foss AttorneyRichard Low ABSTRACT: In a power hammer, and particularly in a mount ing structure therefor, the power hammer has a frame carried by levers which in turn are carried by blocks mounted on a floor. The frame carries damping cylinders pistons which act on a shock-absorbing damping medium within the cylinders, A transmission extends between the levers and the pistons to cause the latter to tend to move into the cylinders to provide shock absorption by the damping medium in the cylinders when the ram of the hammer strikes against work carried by an anvil of the hammer. In this way, the frame is situated over and out of engagement with a floor which is protected against In ury.

1 POWER HAMMER BACKGROUND OF THE INVENTION The present invention relates to power hammers.

In particular, the invention relates to structure for mounting power hammers in the case where such hammers are required to absorb very heavy blows from the ram.

Power hammers of this general type must be carefully mounted in suitable foundations. Considerable difficulty is encountered in mounting units of such types because of the large dynamic effects of such machines. In order to resist such dynamic effects, most of the power hammers of the referred to types are mounted on special shock-absorbing foundations. The cost for these special foundations is often on the order of 30 percent of the cost of the entire power hammer.

In order to improve the mounting of the frame of such hammers with respect to foundations therefor, it has already been proposed to provide a hammer assembly having a frame mounted on lift pistons which are movable in lift cylinders carried in suitable foundations. The pressure of the fluid within these cylinders is interconnected with the pressure chamber of an operating cylinder situated beneath the piston of the ram of the hammer, such communication being provided by a suitable pipeline having discharge and nonretum valves.

The disadvantage of this type of solution to the problem resides in the fact that it is difficult, if not impossible, to maintain the lift cylinders and the pistons moving therein with their axis remaining precisely parallel to each other. Moreover the lift cylinders and pistons therein are not readily accessible for assembly and maintenance purposes so that considerable difficulties are had in connection with the assembly and the maintenance of the structure. Furthermore, if only two lift cylinders are provided along the longitudinal axis of the hammer, an undesired but unavoidable swinging out of the hammer occurs with respect to the longitudinal axis thereof,

- giving rise to further difficulties.

SUMMARY OF THE INVENTION It is the primary object of the construction which will avoid backs.

More specifically, it is an object of the invention to provide a construction capable of mounting a power hammer in such a way that shocks will not be undesirably transmitted to a floor of a shop where the hammer is situated.

Further, it is another object of my invention to provide a construction which enables the hammer to be supported on the floor of the shop without excavating the floor or providing any costly special foundations for the hammer.

In accordance with the invention, the frame of the hammer is mounted on levers which in turn are carried by blocks that rest on the floor. The frame of the hammer has damping cylinders accommodating a damping medium in their interiors, and pistons are situated in the cylinders to transmit forces to the damping medium therein. A transmission means extends between the levers and the pistons for urging the latter further into the cylinders to transmit shocks to the damping mediums in the cylinders when the hammer operates. With this construction the entire frame is situated above and spaced from the floor while the blocks which directly engage the floor can be of the silent block type in order to minimize transmission of impacts to the floor. The damping medium within the cylinders can take the form of a spring, a hydraulic liquid, a pneumatic gas, or the like.

BRIEF DESCRIPTION OF THE DRAWING The invention is illustrated by way of example in the accompanying drawing which forms part of this application and in which:

FIG. I is a schematic sectional side view of a structure according to the invention; and

FIG. 2 is an elevation of the structure of FIG. I as seen from theright side of FIG. 1.

present invention to provide a the above mentioned draw- 2 DESCRIPTION OF A PREFERRED EMBODIMENT Referring to the drawing in greater detail now, the power hammer illustrated includes a frame I which is in the form of a single unitary structure carrying an anvil 14 on which the work is supported to be worked on by a ram 2 that is guided and controlled in a well known manner which does not form part of the invention.

According to the invention, the frame 1 is carried by a lever means which takes the form of two pairs of two-armed levers 4, each pair carrying between the connected ends of the respective levers pins 3 which extend to the levers from the frame 1 so as to mount the latter on the levers 4 intermediate ends thereof in the manner illustrated. A support means is provided for supporting the levers 4 of the lever means on the floor 8, which support means takes the form of blocks 6 carrying pivot pins 5 which are pivotally connected with outer ends of the several levers 4. These blocks 6 in turn are mounted on silentblocks or shock-absorbing, resilient components 7 which with the elements 6 form the support means that through the pins 5 carry the lever means 4.

At their inner ends the several levers 4 are connected by way of pivot pins 9 with pullrods 10 which form a transmission means transmitting the turning movement of the lever means 4 to a shock-absorbing means. This shock-absorbing means includes the plates 11 connected to the top ends of the pullrods 10 and fixed to the top ends of pistons 12 which are slidable within cylinders 13 that are fixedly carried by the frame 1. Within the cylinders 13 is a suitable damping medium in the form of springs to be pressed on by the pistons 12, compressed air, or a hydraulic liquid which can be controlled in any manner well known with damping devices.

The above-described structure operates in the following manner:

When the ram 2 strikes work carried by the anvil 14, the energy is transmitted to the frame 1 which in turn through the pins 3 and the levers 4 provides a downward pull on the rods 10. These rods then act through the plates 1 l on the pistons 12 to tend to displace the latter further into the cylinders 13 so that in this way the damping medium will absorb the shock.

During the striking of the work by the ram 2, the frame 1, situated over and spaced from the floor 8, evenly balances the transmission forces between the two pairs of two-armed levers 4 which swing easily about the pins of the support means 6,7 within the particular limits allowed by the pressure spring or fluid under pressure within the damping cylinders 13 beneath the pistons 12.

Thus, it will be seen that with the structure of the invention as the frame 1 tends to move downwardly to swing the inner ends of the levers 4 downwardly, these inner ends tend to displace the pistons 12 downwardly into the cylinders 13. Because the lever arms of the pullrods 10 are greater than the lever arms of the pins 3, the pullrods 10 will tend to be displaced downwardly more rapidly and through a greater distance than the pins 3 so that in this way the entire frame is supported by exerting pressure on the damping medium within the cylinders 13.

With such structure of the invention, the frame is maintained out of engagement with the floor 8 and is suspended on the levers 4 hovering, or balanced, on the system of twoarmed levers 4. An impact absorbed by the frame in the case of heavy blows brought about by the ram is absorbed through the balanced levers and the fluid or other damping medium within the cylinders which are fixed to the frame.

In addition to the primary advantage of avoiding the transmission of direct blows to the foundation, the structure of the invention offers additional advantages. Thus, the machine of the invention can be installed on relatively thin concrete floors. Also, it can easily be provided with a bottom ejector. In addition, the entire machine can easily be displaced within the shop in the event that overhauling is required or a change in the manufacturing procedure in a production line or the like requires shifting of the entire power hammer to a new loca tion.

Iclaim:

1. In a power hammer, a frame, shock-absorbing means carried by said frame, a plurality of lever means carrying said frame and situating the latter over and spaced from a floor, support means associated with each of said lever means for carrying said lever means, each of said lever means comprising an arm secured at its outer end to its associated support and transmission means associated with each lever arm inwardly of said outer end for transmitting swinging of said lever arm to said shock-absorbing means when an impact is transmitted from said frame, to thereby protect the floor against forces encountered during operation of the power hammer.

2. The combination of claim 1 wherein the said shock-absorbing means includes a pair of cylinders fixed to said frame and adapted to contain a shock-absorbing medium, and pistons slidable in said cylinders, respectively, for engaging said medium, said support means including blocks engaging the floor and pivotally connected with said lever means and said lever arms being pivotally connected intermediate their ends to said frame, said transmission means including elongated pullrods pivoted to said levers distant from said blocks and operatively connected with said pistons for urging the letter into said cylinders when a ram of said power hammer strikes against an anvil or work thereon, the anvil being carried by said frame.

3. The combination of claim 2 and wherein said blocks are of the silent block type for providing a resilient engagement with the floor.

4. The combination of claim 2 and wherein said shock-absorbing medium in said cylinders is in the form of a yieldable resilient material

Claims (4)

1. In a power hammer, a frame, shock-absorbing means carried by said frame, a plurality of lever means carrying said frame and situating the latter over and spaced from a floor, support means associated with each of said lever means for carrying said lever means, each of said lever means comprising an arm secured at its outer end to its associated support and transmission means associated with each lever arm inwardly of said outer end for transmitting swinging of said lever arm to said shock-absorbing means when an impact is transmitted from said frame, to thereby protect the floor against forces encountered during operation of the power hammer.

2. The combination of claim 1 wherein the said shock-absorbing means includes a pair of cylinders fixed to said frame and adapted to contain a shock-absorbing medium, and pistons slidable in said cylinders, respectively, for engaging said medium, said support means including blocks engaging the floor and pivotally connected with said lever means and said lever arms being pivotally connected intermediate their ends to said frame, said transmission means including elongated pullrods pivoted to said levers distant from said blocks and operatively connected with said pistons for urging the letter into said cylinders when a ram of said power hammer strikes against an anvil or work thereon, the anvil being carried by said frame.

3. The combination of claim 2 and wherein said blocks are of the silent block type for providing a resilient engagement with the floor.

4. The combination of claim 2 and wherein said shock-absorbing medium in said cylinders is in the form of a yieldable resilient material.

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