US3675452A

US3675452A - Device for surface hardening of parts

Info

Publication number: US3675452A
Application number: US20662A
Authority: US
Inventors: Jury Anatolievich Osmolovsky; Anatoly Serafimovich Kizilyaev
Original assignee: Individual
Current assignee: Individual
Priority date: 1970-03-18
Filing date: 1970-03-18
Publication date: 1972-07-11
Anticipated expiration: 1989-07-11

Abstract

A device for hardening the surfaces of parts by means of plastic deformation. The device permits hardening bodies to be admitted by gravity into a chamber from an additional chamber by opening a valve which normally closes a hole between the two chambers. The valve is then closed and a stream of compressed air is admitted to propell the hardening bodies to harden the surface of parts. The hardening bodies can be caused to reenter the additional chamber upon completion of a hardening operation by opening the valve while the stream of compressed air is being applied.

Description

United States Patent Osmolovsky et al.

July 11, 1972 DEVICE FOR SURFACE HARDENING OF PARTS [72] Inventors: Jury Amtnlievieh Oanolovsky, Pisarevsky proezd, 3. kv. 47, Pushkino Moskowskoi Oblasti; Anatoly Senflmovlch Kizilyaev, ulitsa 8 Marta, 7, kv. 118, Ljubertsy Moskovskoi Oblasti, both of U.S.S.R.

[22] Filed: March 18, 1970 [2!] Appl.No.: 20,662

[52] U.S.Cl. ..72/53,5l/ll [5]] Int. Cl. C2ld7/06 [58] FieldolSeare-h ..72/53;29/90, 90.1,901, 90.3,

29/906, 908, DlG. 36; Sill l [56] References Cited UNITED STATES PATENTS 2,70l,408 2/1955 Borger v.72/53 Primary Examiner-Charles W. Lanham Assislanl Examiner-Gene P. Crosby Attorney-Waters, Roditi, Schwartz & Nissen ABSTRACT A device for hardening the surfaces of pans by means of plastic deformation. The device permits hardening bodies to be admitted by gravity into a chamber from an additional chamber by opening a valve which normally closes a hole between the two chambers. The valve is then closed and a stream of compresed air is admitted to propell the hardening bodies to harden the surface of parts. The hardening bodies can be caused to reenter the additional chamber upon completion of a hardening operation by opening the valve while the stream of compressed air is being applied,

ZChiugZDrawlngFigum DEVICE FOR SURFACE HARDENING F PARTS The present invention relates to devices for the surface hardening of parts by plastic deformation and more specifically to devices for the hardening of parts with the aid of hardening bodies activated by a stream of compressed gas.

Devices are known for the hardening of parts by the use of hardening bodies in the form of metal balls propelled by a stream of compressed air. These devices consist of a casing which, together with the surface of the workpiece, forms a chamber for holding the hardening bodies in the process of hardening, and of an apparatus for collecting the hardening bodies on the completion of said process.

The chamber holding the metal balls during the hardening process is in communication with a compressed air line and, through holes in the casing walls, with the ambient atmosphere.

The apparatus for collecting the metal balls on completion of the hardening process is made in the form of an electromagnet whose core is constituted by the casing of the device.

In the known type of device, it is necessary, for holding the metal balls in the chamber after the compressed air supply has been cut off, to switch on the electromagnet. This complicates the design of the device because, apart from the supply of compressed air, it must have a low-voltage D.C. supply.

in addition, for holding the balls during the intervals between the hardening operations, the casing of the device must be kept energized, and this is extremely inconvenient in operation.

An object of the present invention resides in eliminating the aforesaid disadvantages.

A more specific object of the invention resides in providing a device for the surface hardening of parts wherein the apparatus for collecting the hardening bodies after the hardening cycle collects the hardening bodies by utilizing the energy of the compressed gas used for hardening.

The above objects are accomplished by providing a device for the surface hardening of parts with hardening bodies propelled by a stream of compressed gas, said device including a casing open at one said and forming, together with the surface of the part being hardened, a chamber for holding the hardening bodies in the process of hardening, said chamber communicating with the compressed air line and, through holes in the casing, with the atmosphere, and an apparatus for collecting the hardening bodies after the end of the hardening process. According to the invention, the apparatus for collecting the hardening bodies is an additional chamber which communicates with the chamber which holds the hardening bodies during the hardening process through a hole covered by a valve. Additionally, through holes in its wall the additional chamber communicates with the atmosphere.

A device for the cold work hardening of parts realized in accordance with the present invention is simple to manufacture and easy to use in operation.

The invention will next be described in detail by way of example with reference to the accompanying drawings in which:

FIG. 1 is a longitudinal section through a device for the surface hardening of parts according to the invention; and

FIG. 2 is a view in the direction of arrow A in FIG. 1.

In the drawing, a device for the surface hardening of a part 1 (FIGS. 1, 2) comprises a casing 2 mounted in a holder 3. The casing 2 is made of, for example, polyfluoroethylene resin or caprolan. The casing 2 is cone-shaped and its narrower part accommodates a nozzle 4 connected with the compressed air line 5 while its wider open part is in contact with the surface of the part 1 being hardened. The casing 2 and the surface of the part 1 forms a chamber 6 which holds the hardening bodies 7 in the course of a hardening operation. The hardening bodies 7 have the form of metal balls. The hardening bodies can also be constituted by any objects having a rounded shape. They may be made of plastic or other nonmetallic materials.

For putting the chamber 6 in communication with the atmosphere, the walls of the casing 2 have holes 8 whose size is smaller than that of the hardening bodies 7. The compressed air entering the chamber 6 for use in hardening the part 1 escapes through these holes into the atmosphere.

Installed on the wider open part of the casing 2 is a flexible element 9 which, fitting tightly against the surface of the part 1, makes it possible to follow the shape of the surface being hardened. The flexible element 9 has a hole 10 whose shape corresponds to that of the part 1 being hardened. If the surface to be hardened is flat, the hole 10 of the flexible element 9 is round which insures a maximum area for the hardened surface of the part 1. The flexible element 9 is held in the casing 2 and holder3 by a nut 11.

The casing 2 has a threaded hole 12 receiving an apparatus 13 for collecting the hardening bodies 7 after the processing of the surface of the part 1.

The apparatus 13 is made in the form of an additional chamber 14 which communicates with the chamber 6 through the hole 12. The hole 12 is covered by a valve l5. This valve is connected to one end of a rod 16 while the other end of said rod carries a handle l7.

Located on the rod 16 between the handle 17 and the additional chamber 14 is a spring 18 which holds the valve 15 closed.

The walls of the additional chamber 14 are provided with holes 19 communicating it with the atmosphere. The size of these holes is smaller than that of the hardening bodies 7.

The casing 2 and a part of the holder 3 are enclosed by a housing 20 which protects servicing personnel against the escaping jets of compressed air and reduces the level of noise produced when the hardening bodies strike the surface of the part being hardened.

The described device which is provided for the surface hardening of parts operates as follows:

The additional chamber 14 is filled with 70-[00 g balls 7 of 2 or 3 mm. diameter. Then the apparatus 13 is screwed into the hole 12 of the casing 2. The apparatus 13 is set at a certain angle in the casing 2 so that the balls 7 are able to fall into the chamber 6 under their own weight (the valve being open, as shown by dotted lines in FIG. 1).

After installation of the apparatus 13 in the casing 2 of the device, the latter is brought to the surface of the part 1 to be hardened until it fits tightly against it. Then, by a pressing of the handle 17, the valve 15 is opened (shown by dotted lines) and the balls fall under their own weight into the chamber 6.

Being acted upon by the spring 18, the valve 15 returns to the initial position, closing the hole 12 in the casing 2. Then compressed air under a pressure of 3-6 atm. is admitted into the chamber 6. Being discharged at a high speed from the nozzle 4, the air entrains the balls 7 and, having imparted its kinetic energy to them, escapes into the atmosphere through the holes 8. The balls that have acquired a certain velocity, strike the surface of the part 1 and act to harden it.

On completion of hardening of the part 1, the valve l5 is opened by the handle 17, without cutting off the supply of compressed air. The air under pressure rushes into the additional chamber 14 due to the relationship between the total areas of holes 8 and 19 which provides a preferred path of escape for the compressed air, thereby propelling into said additional chamber the balls 7 which are collected in this chamber within a small period of time (not over 15 seconds).

Then the valve is closed and the supply of compressed air from the air line 5 is cut off. This completes the process of hardening the part I and the device is withdrawn from the hardened surface.

For hardening the surface of bodies of rotation, e.g. torsion shafts, the device is secured to the tool holder of a turning lathe (not shown) whereas the parts 1 are set in the lathe centers. Then the part 1 is rotated and the device is moved progressively. This insures the hardening of the entire surface of the part. The flexible element 9 which fits tightly against the surface being hardened prevents the compressed air and the balls from escaping to the outside at the point where part contacts said element.

For fitters work, for instance while straightening sheet metal, the device is held in a vertical position, being pressed against the surface of the part 1 by hand We claim:

17 A device for the surface hardening of parts by the use of hardening bodies propelled by a stream of compressed air supplied through a compressed air line, said device comprising: a casing provided with an opening and forming, together with the surface of said part to be hardened, a chamber for holding said hardening bodies in the course of a hardening operation; a nozzle mounted in said casing at a position remote from said opening, for coupling said chamber with the compressed air line; said casing including a wall provided with holes for communicating said chamber with ambient atmosphere; means for collecting said hardening bodies, after a hardening process, arranged on said casing and having an additional chamber communicating with the first said chamber for receiving and holding said hardening bodies after a hardening process, said additional chamber constantly communicating with ambient atmosphere through holes provided in said means, the total area of the holes in said means being related to the total area of the holes in the wall of said casing to provide a preferred path of escape of the compressed air through the holes provided in said means; and a valve disposed in said additional chamber for selectively separating said additional chamber from the first said chamber, in the course of hardening, as well as after the collecting of said hardening bodies in said additional chamber.

2. A device as claimed in claim 1 further comprising a spring loading said valve, whereby said valve normally maintains said additional chamber isolated from the first said chamber.

Claims

1. A device for the surface hardening of parts by the use of hardening bodies propelled by a stream of compressed air supplied through a compressed air line, said device comprising: a casing provided with an opening and forming, together with the surface of said part to be hardened, a chamber for holding said hardening bodies in the course of a hardening operation; a nozzle mounted in said casing at a position remote from said opening, for coupling said chamber with the compressed air line; said casing including a wall provided with holes for communicating said chamber with ambient atmosphere; means for collecting said hardening bodies, after a hardening process, arranged on said casing and having an additional chamber communicating with the first said chamber for receiving and holding said hardening bodies after a hardening process, said additional chamber constantly communicating with ambient atmosphere through holes provided in said means, the total area of the holes in said means being related to the total area of the holes in the wall of said casing to provide a preferred path of escape of the compressed air through the holes provided in said means; and a valve disposed in said additional chamber for selectively separating said additional chamber from the first said chamber, in the course of hardening, as well as after the collecting of said hardening bodies in said additional chamber.