RU2192944C1 - Apparatus for thermic-impulse deburring of articles - Google Patents

Abstract

FIELD: machine engineering, possibly deburring edges of part surfaces remained after working. SUBSTANCE: apparatus includes base, working chamber with sealing lid and arranged in said chamber heat-removing sleeve with bottom that may be axially moved relative to sleeve. There is cavity between bottom of sleeve and bottom portion of chamber housing. Said cavity is communicated with interjacket space provided between outer wall of sleeve and inner wall of chamber housing. In mean portion along height of said interjacket space ring is mounted with possibility of moving upwards and downwards. Cavity over said ring is filled with compressed air. On lower surface of floating bottom of heat-removing sleeve tie rod is mounted. Said tie rod engages with limit switch mounted outside volume of working chamber. EFFECT: enhanced efficiency, enlarged manufacturing possibilities of apparatus. 1 dwg

Description

 The invention relates to mechanical engineering and is intended to remove burrs remaining after machining at the edges of the intersection of surfaces.

 A device for thermal deburring, containing a working chamber, inside of which a heat sink is mounted with the possibility of axial movement relative to the longitudinal axis. Between the walls of the housing and the side surface of the glass there is a cavity filled with liquid, through which during the combustion of the fuel charge, accompanied by an increase in pressure, a hydrostatic support of the walls of the heat-removing glass is created [1].

 The main disadvantage of this device is that, due to the small value of the liquid compression coefficient, the downward displacement of the glass is small and there are practically no conditions for the liquid to move along the wall, and this reduces the heat removal activity. At the same time, the total force caused by high pressure inside the working chamber and acting on the separation of the bottom of the glass is very large. But for thermotechnical purposes (heat removal), the wall of the glass should be thin, as noted in the materials of the above copyright certificate, and the force acting on the wall is combined, namely: radial compression both from the gases present in the chamber and from the hydraulic fluid backwater; all this is accompanied by a wall stretching under the action of a force tearing off the bottom of the glass. Therefore, the operability of the inner cup and, accordingly, the installation as a whole is very limited.

 The closest in technical essence and the achieved result is a device for thermal deburring, containing a working chamber with a bottom, a cover and nodes of supply and ignition of the fuel mixture. The bottom of the chamber is detachable, has the possibility of axial movement up and down and rests on a liquid, which also fills the inter-neck annular space available in the cylindrical side wall of the working chamber. As the fuel mixture is combusted in the chamber, the bottom moves downward under the influence of increasing gas pressure and, compressing the liquid, increases its pressure in the inter-shell space, thereby increasing the force support of the inner chamber wall, and the wall itself transfers heat to the liquid [2].

 The disadvantage of this invention is that the liquid, which is practically stationary in the inter-neck space, weakly removes heat from the inner glass, and even a small downward displacement of the floating bottom is associated with a noticeable and sharp increase in the force acting from the inside of the chamber on the sealing cover. The increase in force is predetermined by the fact that the annular area of the landing collar, on which the floating bottom of the chamber rests in its initial position, opens to the pressure acting from the inside of the chamber after displacement of the bottom of the chamber. In addition, a sharp shock of the gas pressure front against a sedentary bottom is capable of exciting a hydraulic shock in a liquid, and therefore there is no guarantee that the unit in operation meets the requirements for safe operation.

 The invention is aimed at improving efficiency and expanding the technological capabilities of the device as a whole.

 This is achieved by the fact that in the device for thermopulse deburring of products containing a base, a working chamber with a sealing cover and a heat-removing cup placed in the chamber with a bottom mounted with the possibility of axial movement relative to the cup, and having a cavity between the bottom of the cup and the bottom of the camera body communicating with the inter-cavity space filled with liquid and located between the outer wall of the glass and the inner wall of the chamber body, according to the claimed invention In the middle part of the height, a ring is mounted with the possibility of moving up and down, limiting the liquid level, and the cavity above the ring is filled with compressed air of a given pressure, a rod is mounted on the lower surface of the floating bottom of the heat sink, interacting with an end switch installed outside the volume of the working chamber .

 The mutual arrangement of the air and liquid cavities in the presence of a floating ring in the inter-shell space and the floating bottom of the heat sink provides both hydrodynamic force support to the side wall of the heat sink and intensive heat dissipation due to the flow of a large volume of liquid into the inter-shell space and back with increasing pressure in the chamber during combustion, and then, as the pressure drops, during the removal of combustion products from the working chamber cavity.

 The drawing shows a structural diagram of a device for thermal pulse deburring: the left side of the drawing in the position of the camera "Open", the right - to the end of the combustion process of the fuel charge.

 The device for thermal impulse deburring contains a base 1 on which the housing of the chamber 2 is mounted, in which the heat-removing cup 3 is concentrically located, and the inter-shell space formed by the floating ring 4 is divided into an upper air cavity 5 having a predetermined pressure value and a lower liquid cavity 6, which, through the openings 3 in the glass 3, is in communication with the fluid space 8 located under the floating bottom 9. A rod 14 is mounted on the bottom surface of the bottom 9, capable of moving When the bottom 9 is down, interact with the limit switch 15 located outside the internal volume of the working chamber of the device, and give a command to turn on the node 13 for venting gases from the working cavity of the chamber.

 At the upper end of the housing 2, a sealing cover 10 is mounted, bearing the fuel supply units 11, the ignition 12 and the exhaust 13 of the combustion products from the working cavity of the chamber.

 A device for thermal pulse deburring works as follows.

 In the working cavity of the chamber, workpieces are laid along the inner walls and bottom of the chamber (not shown in the drawing) and closed with a sealed lid 10. The assembly 13 for the removal of combustion products is in the "Closed" position. Through the feed unit 11 fill the chamber with a charge of a combustible gas mixture and set fire to the ignition system 12.

 During the combustion of the gas mixture, the increasing pressure shifts the bottom 9 downward, squeezing the liquid from the space 8 through the openings 7 into the cavity 6; as a result, the ring 4 floats up, increasing the pressure in the cavity 5. In this case, the liquid, washing the outer wall of the glass 3, intensively removes heat from the glass. At the same time, the increasing pressure in the inter-shell space provides hydrodynamic force support to the wall of the heat sink cup 3.

 Since the initial value of the air pressure in the cavity 5 affects the lowering speed of the bottom 9 during the combustion of the fuel, the appointment of one or another value of the initial air pressure determines the time during which the fuel burns, since it is known that the combustion of fuel in an increasing volume of the chamber slows down; With this deceleration, the time needed to heat the burrs to their ignition temperature and complete burnout is won.

 In the lowermost position of the bottom 9, the rod 14 fixed to it engages with the limit switch 15, which commands the opening of the assembly 13 for removing combustion products from the working chamber cavity. Then the camera is opened and the cycle of the device is repeated.

The positive effect of the developed device for thermal pulse deburring is as follows:
1) increased efficiency of the device due to the intensification of heat removal by the steady movement of liquid along the wall of the heat sink glass while providing power hydrodynamic support for this glass; in turn, the air cavity provided in the device absorbs the energy of the shock wave arising in the chamber;
2) it is possible to control the duration of fuel combustion by selecting the initial pressure in the air cavity with an increased course of the bottom of the glass and this restrains the rate of combustion of the fuel for the period of time necessary to heat the burrs to their ignition temperature.

Sources of information
1. A. p. USSR 1808557, class In 23 K 7/06, 28/00, publ. 04/15/93, bull. 14.

 2. A. p. USSR 1779499, class In 23 K 7/06, 28/00, publ. 12/07/92, Bull. 45.

Claims (1)

 A device for thermopulse deburring of products, containing a base, a working chamber with a sealing cover and a heat-removing cup placed in the chamber with a bottom mounted axially movable relative to the cup, and having a cavity between the bottom of the cup and the bottom of the chamber body that communicates with the inter-shell space filled liquid and located between the outer wall of the glass and the inner wall of the camera body, characterized in that in the inter-cavity space in the middle part Height of a ring mounted movably up and down, restricting the liquid level and over the ring cavity is filled with compressed air of a predetermined pressure, the floating glass on the bottom of the heat sink bottom surface mounted rod cooperating with a limit switch, mounted outside the working chamber volume.