US1136313A

US1136313A - Jolt ramming-machine.

Info

Publication number: US1136313A
Application number: US81480114A
Authority: US
Inventors: Willy Caspary
Original assignee: Individual
Current assignee: Individual
Priority date: 1914-01-27
Filing date: 1914-01-27
Publication date: 1915-04-20
Anticipated expiration: 1932-04-20

Description

W. CASPARY.

Patented M11120, 1915.

2 SHEETS-SHEET 1.

I'HE NOVIS PEYERS (30., PHOTO-LITHPH WASHINGTOPLILL C4 W. CASPARY.

JOLT RAMMING MACHINE.

APPLICATION FILED JAN.27. 1914.

Patented Apr. 20, 1915.

Z SHEETS-SHEET 2.

WITNESSES INVENTOR HE NORRIS PETERS 60., PHOTO-LITHQ. WASHINGTON. D. Cv

WILLY CASPAEY, OF DURLACH, GERMANY.

JOLT RAMMING-MACHINE.

Specification of Letters Patent.

Patented Apr. 20, 1915.

Application filed January 27, 1914. Serial No. 814,801.

To all whom it may concern:

Be it known that I, WILLY CAsPARY, a subject of the King of Prussia, residing at Durlach, Baden, in the Empire of Germany, prays that Letters Patent may be granted to him for the new and useful Improvements in Jolt Ramming-Machines, of which the following is a specification.

This invention relates to jolt ramming machines and it has for one of its primary objects the provision of a novel arrangement of jolt ramming machine and operating means therefor which is economical and effective in operation and which has the advantages of the fluid pressure actuated and positively actuated types of jolt ramming machines but which has none of the disadvantages of such types. Another object of the invention resides in the provision of a novel form of operating means which permits of regulation of the intensity of the impact or jolt of the machine, and one in which vibration of the machine and also of the supporting structure therefor is reduced to a minimum. More specifically stated my invention contemplates an improved pneumatically actuated jolt ramming machine.

The foregoing, together with such other objects as may hereinafter appear, or are incident to my invention I attain by means of a construction, the preferred embodiments of which I have illustrated in the accompanying drawings, wherein- Fig. 1 is a vertical section through one form of olting machine which embodies my invention; Fig. 2 is a vertical section of another form of my invention; Fig. 3 is a section taken on the line III-III of the device shown in Fig. 2; Fig. 4: is an enlarged sectional showing of a detail of the form of apparatus shown in Figs. 2 and 3; Fig. 5 is a section taken on the line V of Fig. 4; and Fig. 6 is a section taken on the line VI of Fig. 3 but drawn on a larger scale.

Jolt ramming machines of the fluid actuated type usually comprise a cylinder in which is mounted a reciprocating piston or plunger which carries a mold table and a which is adapted to impact on the cylinder on its downward stroke. This type of machme 1s actuated by the introduction of fluid pressure into the cylinder beneath the plunger and requires, in addition to an independent air compressor or other independent source of pressure supply, considerable pipmg from which there is a continuous loss of pressure through leakage, all of which renders machines of this type expensive. In jolt ramming machines of the mechanically actuated type, that is, machines which are positively operated through mechanical means, there is rapid wear because of the vibrations and other stresses necessarily incident to this type of apparatus. This re sults in decreased efl iciency and shortens the life of the machines. My invention is designed to overcome these difficulties and to this end I provide the following mechanism.

Referring now to Fig. 1 of the drawings, it will be seen that the apparatus comprises a main casting 7 the upper portion of which is formed into a cylinder 8, open at the top. Mounted in the cylinder 8 is a piston 9 which is reciprocated by means of a crank shaft 10 through the medium of the usual connecting rod 11. The crank shaft 10 is mounted in the frame 7 beneath the cylinder 8 and carries at one end a fly wheel 12, which also serves as a means for imparting rotary movement to the shaft, a belt drive from any suitable source of power being preferably employed. Intermediate its ends the cylindrical portion 8 of the frame 7 is provided with an annular flange 13 which serves as an impact anvil, and the exterior of the cylindrical portion above such flange turned down to fit the interior of a cylinder 14 depending from the lower face of the mold table 15. When the table 15 is in normal position, that is, lower position, the lower edges of the cylinder 14 rest upon the impact anvil 13, the length of the cylinder 1% being such that a clearance space 16 is provided between the lower face of the table 15, the top of the cylinder 8, and the upper face of the piston 9 when the latter is in upper position. The chamber 17 of the casing or frame 7 beneath the cylinder 8 and through which shaft 10 extends, is preferably made air tight. A by-pass 18 is provided in the wall of the cylinder 8 and extends from the top thereof to the bottom where it opens into the chamber 17; mounted in the bypass is a check valve 19 which is normally held on its seat by means of a spring 20, the valve being arranged to permit a flow of air to the space above the piston but preventing flow from such space into the chamber 17; and a screw 21 is provided whereby to unseat the valve 19 for purposes of regulation as will further appear.

The operation of the apparatus is as follows: On the up stroke the piston 9 compresses the air in the space between the table and the top of the piston since the air is confined therein by the valve 19, and the table 15 is lifted on a cushion of compressed air.

' After the piston reaches the upper extreme of its travel, the upward movement of the table continues by virtue of the expansion of the confined compressed air and by its own momentum. By the time the table has come to rest, the piston has partially completed its downward movement and the table falls by the action of gravity and impacts against the flange or anvil 13, thereby effecting the ramming of the mold or molds carried on the table. This operation is repeated with every reciprocation of the piston.

The advantage obtained by the provision of the by-pass and check valve is that the formation of a vacuum or a so-called partial vacuum, in the space above the piston is prevented. That there is a tendency to form a vacuum will be clear from the fact that during a certain period of the movement of the table and the piston, the two are separating. During this period air is drawn from the chamber 17 through the by-pass into the space above the piston. The presence of a vacuum or a partial vacuum, so-called, in the space above the piston would result in accelerating the downward movement of the table and in increasing the force of the impactto an undesirable degree. By providing a flow between opposite ends of the piston, the mold table falls by action of gravity alone. It will be obvious that the valvular arrangement also affords a means for regulating the force of the impact, this being accomplished by adjusting the screw 21 so as to slightly unseat the valve 19, thereby per mitting a small leakage from the space above the piston into the chamber 17, as a result of which the upward movement of the table will be restricted with a consequent reduction in the force of the impact when the table falls. That this is the case, will be clear from the fact that the cushion of air will-not act as effectively when there is leakage, and will therefore not raise the table as high. It will also be apparent that in cases where a number of machines are operated from one source, any one ofthe machines can be temporarlly cut out by completely unseating the valve 19 and permitting a free, unobstructed flow between opposite ends of the piston, in which case the table will not be moved by the piston.

It will be apparent that the operation of the apparatus is economical and effective, and that beside the advantages incident to the ability to regulate the force of the impact, the construction is such as to eliminate to a large extent excessive vibration of the machine and the foundry floor.

In the type of machine described, the jolt is obtained by the falling or dropping of the table onto an anvil or impact member. In the construction shown in Figures 2 and 3, the jolt is imparted by a blow delivered in an upward direction, the general construction, however, being substantially the same. As in the construction previously described, the framework 7 is provided at its upper portion with a cylinder 8, but the cylinder 14: on the table 15, however, works within the cylinder 8 instead of on the outside thereof, and working within the cylinder 14: is a hollow piston which in this construction constitutes a movable impact member 22. The piston 9 reciprocates within the impact member and operates through a cushion of air to elevate the impact member in the same manner as the table is elevated in the construction of Figure 1. A small space 16 is provided between the lower face of the impact member and the upper face of the piston 9, and a by-pass 18 opens at the top into such space and at the bottom into the chamber 17 said by-pass being controlled as before by means of valve mechanism, which vill be further described.

The operation of this embodiment of the invention is as follows. On the upward stroke of the piston 9, the air confined in the space above the piston is compressed and the impact member 22 is moved upwardly along with the piston, the movement of the impact member continuing after the piston has reached the upper extreme of its movement and has traveled downward a portion of its return stroke. In rising, the impact member 22 impacts against the table 15 and effects the ramming of the mold. The impact member comes to rest and falls by the action of gravity in the manner previously described. In the meantime, the table 15 has moved upwardly a slight distance and then falls, the downward movement of the table 15 being cushioned on the air confined between the end of the cylinder 14 and the bottom of the cylinder 8. The table thus returns to initial position without a jolt. While the impact member 22 is falling, the piston 9' has completed its downward stroke and is again moved upwardly and the downward movement of the impact member is arrested by the cushion of air above the piston. As the upward movement of the piston continues, the impact member is again projected upward in the manner described, This form of apparatus is particularly, adapted for use in connection with large machines in the operation of which it is undesirable to have the impact taken directly upon a portion of the apparatus. It will be apparent that in this construction, the impact is delivered by the upward blow of what may be termed a floating impact member which in itself imparts no jolting to the apparatus because of its support on the cushion of air above the piston. The advantages of this construction will be apparent. It will be noted that a number of leakage ports 23 are provided in the walls of the cylinder 14 closely adjacent the lower face of the table 15, the object being to permit a. free circulation above the impact member, thereby preventing the formation of a vacuum above the impact member on the downward stroke of such member, and also preventing the confinement of air above the impact member which would take away from the sharpness of the blow delivered to the table by the impact member.

Attention is now directed to Figs. 4;, 5, and 6 which are enlarged sectional views of they by-pass 18 and valve mechanism pro-- vided in this type of apparatus. The valve 19 in this construction is also preferably of the check valve type and is a circular plate, the edges of which are engaged and guided by several ribs 19 projecting into the valve chamber (see particularly Fig. The valve permits a flow from the lower chamber to the chamber 16 and adjustment is afforded by the screw 21 by means of which the valve may be opened to any desired degree. The spring 24: is provided in order to insure the seating of the valve when the screw 21 is retracted. By a slight opening of the valve, the force of the impact or jolt may be regulated by the change in the throw of the impact member 22, and by moving the valve to wide-openposition, the movei'nent of the impact member is stopped as before.

[an advantage common to both types of apparatus resides in the fact that heat losses due to compression. and expansion are to a large extent avoided. The compression and expansion of air takes place in the same space and a considerable portion of the heat that is formed on compression is taken up when expansion talres place, which eliminates the necessity of water cooling and reduces power losses.

What I claim is:

1. A jolt ramming molding machine comprising in combination with a movable j olting member, a reciprocatory piston, the move able member and piston being arrangedto arovide a cushion of air therebetween, and means for reciprocating the piston whereby to impart movement to the-movable member through the cushion of air.

2. A olt ramming molding machine comprisingin combination with a movable jolting member mounted for free vertical movement, a reciprocatory piston working within said member but spaced apart therefrom to provide a chamber for confining a cushion of air, and means for reciprocating the piston; whereby to impart upward movement to the said member through the medium of the cushion of air.

3. A jolt ramming molding machine comprising in combination with a movable jolting member mounted for free vertical movement, a reciprocatory piston for actuating the jolting member, there being a space between the piston and said member for con fining a cushion of air, means for reciproeating the piston whereby to impart upward movement to the jolting member through the medium of the cushion of air, and means for preventing the formation of a vacuum in said space on the downward stroke of the piston. r

4. A jolt ramming molding machine comprising in combination with a movable jolting member mounted for vertical movement, a reciprocatory piston for operating said member, an air chamber above Said piston and between the piston and movable member and an air chamber below said piston, a bypass from the upper to the lower chamber, a valvular device controlling said by-pass, and means for reciprocating the piston, said piston imparting movement to the movable member through the medium of the air in said upper chamber. I

A jolt ramming molding machine comprising in combination with a movable jol ing member, a reciprocatory member for actuating said jolting member, and an in tel-posed yielding movement-trausmittingmeans through the medium of which the reciprocatory member imparts movement to the jolting member.

6. A jolt ramming molding machine comprising in combination a substantially vertical cylinder, a mold table having a depending cylindrical portion slidably guided on the exterior of the cylinder for free vertical movement, and a piston reciprocating within the cylinder for operating the table, there being a. space between the piston and the table to provide a cushion of air therebetween.

7. A jolt ramming machine comprising in combination a movable mold support, a movable actuating 'member adapted to impart movement to the support, and an interposed yielding movement-transmitting means through the medium of which the said member imparts movement to the support.

8. A jolt ramming machine comprising in eembinatio'n a movable mold support, and signed my name in the presence of the two .a movable actuating member thereforgthere subscribed Witnesses.

being a'cushion of air interposedbetween r i V r said member and said "support whereby ILL} CASPARX' 5 movement is transmitted to the latter When Vitnesses:

said member is moved. S. S. BERGER, In testimony whereof I have hereunto S. HEPTIAM.

v G'opies'of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

7 Washington, D. C.