MECHANICAL INTERFACE CONNECTION FOR VACUUM EJECTORS, AND A MODULAR ASSEMBLY FOR SUPPLYING NEGATIVE PRESSURE TO AN INDUSTRIAL PROCESS BY MEANS OF AT LEAST ONE VACUUM EJECTOR DRIVEN BY COMPRESSED AIR

Abstract: The assembly for generating a negative pressure in an industrial process according to the invention is characterized in that the interconnected units (1, 2, 3..) are formed with wedge-shaped connections (13, 14) in their mutually contacting surfaces. Intermediate units in the assembly, such as the ejector housing (2) of the drawing, are formed in each contact surface thereof with the same type of connections: accordingly, in one end the unit comprises a female connection (14) on one side thereof, and a male connection (13) on the opposite side, whereas the other end of the unit comprises a male connection on the first said side and a female connection on the opposite side. The connections comprise inclined slide surfaces (11, 12), providing a hook mount which presses the units together in a wedging effect as the units are axially displaced relative to each other, the displacement being produced by means of a bolt (10) acting between the units.

Description: TITLE Mechanical interface connection for vacuum ejectors, and a modular assembly for supplying negative pressure to an industrial process by means of at least one vacuum ejector driven by compressed air. TECHNICAL BACKGROUND The invention is concerned with a mechanical interface, or more specifically a snap on connection or quick-coupling for associated units incorporated in a modular assembly having at least one vacuum ejector adapted to provide a negative pressure, in accordance with the preamble of claim 1. The present invention also refers to a modular assembly for supplying a negative pressure to an industrial process, said assembly comprising at least one vacuum ejector driven by compressed air and operative for evacuating air from said process in accordance with the preamble of claim 5. Vacuum ejectors that are driven by compressed air are specifically advantageous for shifting operational conditions in industrial environments, due to their small dimensions and a construction that needs little maintenance. Operationally adapting the ejectors may include combining several ejectors into an assembly that provides a desired effect. Such assemblies may also comprise additional devices for connecting the assembly to the process that is driven by the ejectors, or to other external equipment. In connection herewith there is a need and desire to reduce time and costs for assembling the system, and to eliminate any mechanical or set-up problems that may arise when incorporating supplemental couplings, fittings and additional adapter elements. OBJECT OF INVENTION The object of this invention is to provide a mechanical interface connection between units that are incorporated in an assembly for supplying a negative pressure to an industrial process. Another object of the invention is to pro- vide a modular assembly having substantial flexibility while being adapted to shifting operational conditions of the industrial process. SUMMARY OF THE INVENTION Briefly the invention suggests that adjacent units, incorporated in the assembly, in contact surfaces thereof are formed with snap-on connections resembling a mirrored hook mounting. The connection provides a wedging action upon axial relative displacement of the connected units, the coupled units being axially arrested by means of a locking bolt. The invention is further disclosed below, reference being made to the attached drawing. DETAILED DESCRIPTION OF INVENTION In the drawing, an assembly is illustrated comprising three interconnected vacuum ejector units 1, 2 and 3. The shown assembly will exemplify the invention which may be applied for connecting any desired number of units. An ejector house 1 is formed on its bottom side with seat mountings for connecting to a mount support, not further shown. An ejector body 4 adapted to operate by compressed air is accommodated in the housing 1 , the ejector body carrying a silencer 5 protruding from one end of the ejector housing. In the opposite end thereof, compressed air is supplied and forced through the ejector 4 as illustrated by the arrow P, whereby negative pres- sure is generated in an annular space 6 defined about the ejector 4 and communicating with the process such as to be operative for evacuating air from the process. A second ejector housing 2 is connected to the housing 1 and accommodat- ing a second ejector body 4'. Channels 7 for compressed air and channels 8 for evacuated air are formed to establish fluid flow communication between the two ejector housings 1 and 2. A modular adapter 3 is attached to the second ejector housing 2 and comprising connections 9 that are formed for connecting the vacuum channels 8 to an industrial process (not shown), driven by the assembly. A quick- coupling is formed at the interface between connected units 1 , 2 and 3, by which the units are snapped together and locked in the interconnected position by means of a bolt 10. Said quick-coupling may be compared to a hook mount and is formed to generate a wedging action upon axial relative displacement of adjacent units 1 and 2, 2 and 3, respectively. Such axial displacement into an arrested position is performed through the bolt 10, extended axially upon rotation to act between interconnected units. Sloping slide faces 1 1 and 12, respectively, are formed at the end portions of opposite and contacting, planar surfaces of the units. One of the sloping faces 1 1 extends above the unit surface, and the other sloping face 12 is extended below said surface. The sloping face 1 1 is arranged on a wedge- formed protrusion 13, providing a male connection, and the sloping face 12 is arranged on a wedge-formed recess 14, providing a female connection. The recess 14 provides a gap 15 having a width sufficient for the protrusion 13 to be inserted in the recess 14 without the sloping faces 1 1 and 12 contacting each other. The sloping faces are formed to have an inclination relative to the planar contact surfaces of the units in the order of 45°, or less. A threaded bore 16 extends from the end plane of the units into the recess 14 for a threaded engagement with the bolt 10, such that the bolt engages the outer side of the wedge-formed protrusion 13 for relative displacement of the interconnected units into a locking position. Upon displacement, the inclined slide faces 12 and 13 cooperate for pressing together the opposing surfaces of adjacent, interconnected units. Seals 17, such as O-rings 17, may be inserted in grooves formed on the planar surfaces for providing an air-tight enclosure of the channel paths 7 and 8, and a certain elasticity in the attachment. Even if not explicitly shown herein, it will be understood that interconnected units also may be formed with identical female and male connections. In such alternative embodiment the bolt 10 may be inserted from any desired end or from both ends of the assembly, in order to lock the units in the as- sembled position. In yet another embodiment, the units may be formed in one contact surface thereof with two female connections, and in the other surface with two male connections. The shown embodiment wherein one of the sliding faces pro- trudes above the contact surface of the unit, and the other sliding face is recessed below the contact surface, is the preferred embodiment due to material savings and the compact assembly made possible hereby. The assembly for generating a negative pressure in an industrial process according to the invention is characterized in that the interconnected units are formed with wedge-shaped connections in their mutually contacting surfaces. Intermediate units in the assembly, such as the ejector housing 2 of the drawing, are formed in each contact surface thereof with the same type of connections: accordingly, in one end the unit comprises a female connection 14 on one side thereof, and a male connection 13 on the opposite side, whereas the other end of the unit comprises a male connection on the first said side and a female connection on the opposite side. The connections comprise inclined slide surfaces 1 1 , 12, providing a hook mount which presses the units together in a wedging effect as the units are axially dis- placed relative to each other, the displacement being produced by means of a bolt acting between the units.

Claims: CLAIMS 1. A mechanical interface, connecting units (l ,2,3)incorporated in a modular assembly adapted to supply negative pressure for an industrial process, the assembly comprising one or several vacuum ejectors (4,4') each accommodated in one of said units and driven by compressed air such as to be operative for evacuating air from said process, the ejectors being in mutual fluid flow communication through channels (8) formed in the units, characterized in that said mechanical interface being defined in contact surfaces of adjacent, interconnected units of the assembly, the interface comprising inclined slide faces (1 1 , 12) formed for mutual engagement and for providing a wedging action upon relative, axial displacement of the units into an interlocking position upon assembly. 2. The mechanical interface connection of claim 1 , wherein the inclined slide faces are formed at the end portions of the contact surface of each unit such that one of the slide faces (1 1) extends above the surface, and the other slide face (12) extends below said surface. 3. The mechanical interface connection of claim 2, wherein one of the slide faces ( 12) is formed in a recess, providing a female connection ( 14), and the other slide face (1 1) is formed on a protrusion, providing a male connection (13) in opposing contact surfaces, respectively, of the unit. 4. The mechanical interface connection of claim 2, wherein a bolt ( 10) acting between the interconnected units (1 and 2; 2 and 3; etc.) locks the units axially in their interconnected positions. 5. A modular assembly adapted for supplying a negative pressure by means of one or several vacuum ejectors driven by compressed air, the assembly comprising one or several vacuum ejector housings (1 ,2,3) in fluid flow communication through channels formed therein, characterized in that each housing of the assembly comprising mating connections (13, 14) defined in opposing contact surfaces of the housing, the connections having inclined slide faces (1 1, 12) in mutual engagement upon relative axial displacement of the housings, the connections being locked in the engaged position by means of a bolt (10) acting between the housings in the interconnected po- sition. 6. The modular assembly of claim 5, wherein intermediate housings (2) of the assembly are formed on one side thereof with a female connection ( 14) in a first end and a male connection (13) in the other end, and on the opposite side are formed with a male connection (13) in the first end and a female connection (14) in the other end, as seen longitudinally of said housing.

Inventors: TELL PETER, TELL, PETER
Applicants: PIAB AB, TELL PETER, TELL, PETER
Application year: 2000
Main classification: F04F5
IPC codes: F04F5