EP0031344B1 - Machine with multi tandem free pistons - Google Patents

Machine with multi tandem free pistons Download PDF

Info

Publication number
EP0031344B1
EP0031344B1 EP80901199A EP80901199A EP0031344B1 EP 0031344 B1 EP0031344 B1 EP 0031344B1 EP 80901199 A EP80901199 A EP 80901199A EP 80901199 A EP80901199 A EP 80901199A EP 0031344 B1 EP0031344 B1 EP 0031344B1
Authority
EP
European Patent Office
Prior art keywords
cylinders
machine according
cross
pistons
compressor
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
EP80901199A
Other languages
German (de)
French (fr)
Other versions
EP0031344A1 (en
Inventor
Henry Benaroya
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Publication of EP0031344A1 publication Critical patent/EP0031344A1/en
Application granted granted Critical
Publication of EP0031344B1 publication Critical patent/EP0031344B1/en
Expired legal-status Critical Current

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01B—MACHINES OR ENGINES, IN GENERAL OR OF POSITIVE-DISPLACEMENT TYPE, e.g. STEAM ENGINES
    • F01B11/00—Reciprocating-piston machines or engines without rotary main shaft, e.g. of free-piston type
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
    • F02B71/00—Free-piston engines; Engines without rotary main shaft

Definitions

  • the present invention relates to multi-tandem free piston machines, comprising several pairs of parallel engine cylinders, each cylinder containing two opposite free engine pistons, integral with compressor pistons.
  • the invention more particularly relates to a multi-tandem machine with free pistons comprising a frame, an internal movable assembly comprising a central cross member transverse to an axis of the frame, guided in translation so as to be able to move with an alternating movement the along said axis, carrying, on each side, four internal driving pistons displaceable along the driving cylinders arranged at the apexes of a rectangle and two compressor pistons sliding in internal compressor cylinders whose axes pass outside said rectangle, an external mobile assembly comprising two external crosspieces connected by at least one tie rod, each carrying four external engine pistons displaceable in four of said engine cylinders and two compressor pistons sliding in external compressor cylinders, and means for synchronizing the reciprocating movement of the two crews.
  • the invention aims to provide a multi-tandem machine whose frame has a very high rigidity, ensuring satisfactory guidance of the crews while allowing easy disassembly of the cylinders, and in particular of the cylinders which have a large axial dimension.
  • the invention provides a machine in which the frame comprises a base, an upper base connected by at least one central monobloc structure on which the internal compressor cylinders are fixed.
  • the machine comprises preferably two frames connecting the base and the base, arranged symmetrically with respect to a median plane of the frame and on which the external compressor cylinders are fixed by their face facing the median plane, the opposite faces of said cylinders external compressors which can be connected by plates.
  • each frame can be designed to constitute, with the base, the box spring and a casing which it contains and which delimits a space containing the corresponding external cross-member, a supply manifold for the corresponding external compressor cylinders.
  • the sleepers must be provided with guide means.
  • a first solution consists in providing them with bearings sliding on fixed guide tubes.
  • the machine shown in fig. 1 comprises a frame, an internal mobile assembly and an external mobile assembly, as well as fixed gas circulation pipes.
  • the frame comprises a base 10 and an upper base 11 substantially of the same length, connected by an internal monobloc structure 12 and two frames 13, symmetrically arranged with respect to the median plane III.
  • This constitution supplemented by cruciform structures 14, gives the frame very great rigidity.
  • the frame carries, by means which will be described later, four driving cylinders, two of which, 15a and 15b, appear in FIG. 1, on each side of the median plane III.
  • the axes of the four cylinders 15a, 15b, 15c and 15d are arranged at the corners of a rectangle 16 which, in the illustrated embodiment, is arranged with its large side vertically.
  • Two internal double-acting compressor cylinders 17a and 17b are mounted one on each side of the central monobloc structure 12. The axes of these cylinders 17a and 17b intersect the small median 18 of the rectangle 16.
  • To each frame 13 are fixed two compressor cylinders 18a and 18b also double acting.
  • the axes of the cylinders 18a and 18b intersect the large median 19 of the rectangle 16, outside of the latter.
  • the internal mobile assembly comprises a central cross member 20 (FIG. 3) which, due to the forces to which it is subjected, will generally be machined in a single forged part.
  • the cross member 20 is fixed to an axial guide tube 21, carried by bearings (not shown) spaced from each other by a distance at least equal to three times the diameter of the tube, and fixed to the frame.
  • the cross member has two opposite horizontal arms fixed to the rods 29 of the pistons of the internal compressor cylinders 17a and 17b. Two protrusions of the cross are attached to the rods of the pistons of the internal engine cylinders 15a, 15b, 15c and 15d.
  • the central monobloc structure makes it possible to avoid projections and dispersions. important lubricant.
  • this central structure is constituted by a cage 22, inside which is placed a casing 23 enveloping the span and of sufficient axial dimensions to allow the movement thereof.
  • the casing 23 is obviously provided with seals for the passage of the rods 29 connecting the cross-member to the pistons.
  • This casing or the cage can carry the bearings of the guide tube 21.
  • the external mobile assembly has a symmetrical constitution with respect to the median plane III. It comprises two external crosspieces 24 (FIG. 4), the span of which can be made much smaller than that of the central crosspiece 20, which offers several advantages. On the one hand, there is a tendency to balance the masses of internal and external crews inherently. On the other hand, the stresses undergone by the external crosspieces are significantly reduced, particularly during the driving phase, when forces of opposite signs are transmitted by the rods of the external driving pistons 25a, 25b, 25c and 25d and the tie rods 26a and 26b of connection between the crosspieces 24, placed in line with the rods of the pistons of the compressor cylinders 18a and 18b. This arrangement of the tie rods allows them to pass outside the central cross member 20. It is consequently possible to give them a one-piece construction and to allow relatively easy disassembly of the cross member 20.
  • the cross members 24, like the cross member 20, are enclosed in a casing 27 provided with sliding seals providing passage to the piston rods and the tie rods. They are provided with guide tubes 28 sliding in bearings not shown. These bearings can be carried by the casing 27 or by a cage 30 which surrounds it and reinforces the frame carrying the compressors.
  • This device comprises two toothed wheels 31 (fig. 4 and 5) placed in the median horizontal plane of the machine. Each wheel 31 meshes with two racks 32 and 33.
  • the racks 32 are fixed to the central cross member 20 while the racks 33 are fixed to one of the external cross members 24.
  • the two wheels 31 are placed on the same side of the median vertical plane of the machine so as not to constitute with the tie rods 26 a hyperstatic system and they are mounted on bearings having an elasticity making it possible to absorb shocks.
  • the fixing of the different cylinders is carried out by means which limit the overhangs.
  • the external compressor cylinders 18a and 18b are fixed by their internal face, adjacent to the cross-member. This face is fixed by bolts which can also serve to retain the valve-holder plates, on the corresponding frame 13.
  • This frame, the depth of which is close to the thickness of the cross-member 24, is itself fixed between base 10 and box spring 11. It is reduced in the middle by a cruciform structure which will be described later.
  • the rigidity of the assembly can be increased by connecting the bottoms of the cylinders 18a and 18b by a plate 34 (fig. 1).
  • the fixing of the internal compressor cylinders 17a and 17b poses a problem which is not found in the case of the external compressor cylinders 18a and 18b. Indeed, it is necessary that the access to the injectors of the engines is possible and that one can disassemble the engine cylinders without important preliminary works and preferably in block.
  • the compressor cylinders 17a and 17b are fixed by flanges on lateral parts of the cage 22, provided for this purpose in very thick sheet metal (40 mm for example).
  • the compressor cylinders can have a true symmetry of revolution with regard to the cooling water circuits and the envelope of compressed air which they discharge, which is very favorable for the reduction of thermal stresses. .
  • the driving cylinders 15a to 15d are each placed in one of the dihedrons of the cruciform structure 14. They can be introduced by simple translation and rotation in the horizontal plane. They are thus introduced into their sweeping pants, previously fixed to the one-piece structure.
  • a cradle facilitating fixing is provided around the water envelope of the central ring of each engine cylinder.
  • casings 23 and 27 make it possible to collect the lubricating oil from the bearings, therefore to reduce losses and contamination by the oil.
  • the oil is collected in the bottom of the casings 23 and 27 and it is evacuated by automatic bleeders before being mixed again with the excess oil from the engine cylinders.
  • Such oil outlets 35 and 36 appear in FIGS. 3 and 4.
  • the collectors 43 are provided with refrigerants 45 (FIG. 1) and flow into sweep collectors 46 which in turn supply all the engine cylinders 15a-d.
  • the MP compressor cylinders placed to the right of the median plane, supply a medium pressure manifold (not shown in the figure). A fraction of the air admitted to this manifold MP is sent to an air turbine driving the turbo-blower. The rest of the air is mixed with the exhaust gases coming from the engine cylinders 15a-d and feeds a gas turbine coupled to the load, constituted for example by an alternator.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Compressors, Vaccum Pumps And Other Relevant Systems (AREA)
  • Molds, Cores, And Manufacturing Methods Thereof (AREA)
  • Casting Devices For Molds (AREA)

Abstract

A machine with free pistons comprising a frame, an inner moving assembly comprising a central cross bar and translatingly guided so as to effect a reciprocating motion along the frame axis and an outer moving assembly comprising two outer cross bars connected by at least one brace rod. The frame comprises a base (10) and a head (11) connected by at least one central monoblock structure. The inner moving assembly comprises four inner motor pistons movable along motor cylinders (15a-15d) arranged at the top of a rectangle and two compressor pistons sliding within the compressor cylinders (17a-17b) of which the axis pass outside said rectangle.

Description

La présente invention concerne les machines à pistons libres multi-tandem, comportant plusieurs couples de cylindres moteurs parallèles, chaque cylindre contenant deux pistons moteurs libres opposés, solidaires de pistons compresseurs.The present invention relates to multi-tandem free piston machines, comprising several pairs of parallel engine cylinders, each cylinder containing two opposite free engine pistons, integral with compressor pistons.

L'invention a plus particulièrement pour objet une machine multi-tandem à pistons libres comprenant un bâti, un équipage mobile interne comprenant une traverse centrale transversale à un axe du bâti, guidé en translation de façon à pouvoir se déplacer d'un mouvement alternatif le long dudit axe, portant, de chaque côté, quatre pistons moteurs internes déplaçables le long des cylindres moteurs disposés aux sommets d'un rectangle et deux pistons compresseurs coulissant dans des cylindres compresseurs internes dont les axes passent hors dudit rectangle, un équipage mobile externe comprenant deux traverses externes reliées par au moins un tirant, portant chacune quatre pistons moteurs externes déplaçables dans quatre desdits cylindres moteurs et deux pistons compresseurs coulissant dans des cylindres compresseurs externes, et des moyens de synchronisation du mouvement alternatif des deux équipages.The invention more particularly relates to a multi-tandem machine with free pistons comprising a frame, an internal movable assembly comprising a central cross member transverse to an axis of the frame, guided in translation so as to be able to move with an alternating movement the along said axis, carrying, on each side, four internal driving pistons displaceable along the driving cylinders arranged at the apexes of a rectangle and two compressor pistons sliding in internal compressor cylinders whose axes pass outside said rectangle, an external mobile assembly comprising two external crosspieces connected by at least one tie rod, each carrying four external engine pistons displaceable in four of said engine cylinders and two compressor pistons sliding in external compressor cylinders, and means for synchronizing the reciprocating movement of the two crews.

Une machine similaire est décrit dans la publication PCTWO 80/02442.A similar machine is described in the publication PCTWO 80/02442.

L'invention vise à fournir une machine multi-tandem dont le bâti présente une rigidité très élevée, assurant un guidage satisfaisant des équipages tout en autorisant un démontage aisé des cylindres, et notamment des cylindres qui ont une dimension axiale importante.The invention aims to provide a multi-tandem machine whose frame has a very high rigidity, ensuring satisfactory guidance of the crews while allowing easy disassembly of the cylinders, and in particular of the cylinders which have a large axial dimension.

Dans ce but, l'invention propose une machine dans laquelle le bâti comprend un socle, un sommier supérieur reliés par au moins une structure monobloc centrale sur laquelle sont fixés les cylindres compresseurs internes. La machine com- , porte de préférence deux cadres reliant le socle et le sommier, disposés symétriquement par rapport à un plan médian du bâti et sur lesquels les cylindres compresseurs externes sont fixés par leur face tournée vers le plan médian, les faces opposées desdits cylindres compresseurs externes pouvant être reliées par des plaques.To this end, the invention provides a machine in which the frame comprises a base, an upper base connected by at least one central monobloc structure on which the internal compressor cylinders are fixed. The machine comprises preferably two frames connecting the base and the base, arranged symmetrically with respect to a median plane of the frame and on which the external compressor cylinders are fixed by their face facing the median plane, the opposite faces of said cylinders external compressors which can be connected by plates.

L'invention trouve une application particulièrement importante dans les installations de production d'énergie comprenant une machine à pistons libres, une turbine à gaz qui reçoit les gaz d'échappement des cylindres moteurs et un compresseur qui fournit aux cylindres compresseurs de l'air à une pression supérieure à la pression atmosphérique, par l'intermédiaire d'un refroidisseur classique. Dans ce cas en effet, chaque cadre peut être conçu pour constituer, avec le socle, le sommier et un carter qu'il contient et qui délimite un espace contenant la traverse externe correspondante, un collecteur d'alimentation des cylindres compresseurs externes correspondants.The invention finds a particularly important application in energy production installations comprising a free piston machine, a gas turbine which receives the exhaust gases from the engine cylinders and a compressor which supplies the compressor cylinders with air at a pressure higher than atmospheric pressure, via a conventional cooler. In this case, in fact, each frame can be designed to constitute, with the base, the box spring and a casing which it contains and which delimits a space containing the corresponding external cross-member, a supply manifold for the corresponding external compressor cylinders.

Les traverses doivent être munies de moyens de guidage. Une première solution consiste à les munir de paliers glissant sur des tubes de guidage fixes. Toutefois, pour une installation de grande puissance, il est plus avantageux de constituer les moyens de guidage par un ou plusieurs tube(s) fixé(s) à la traverse et se déplaçant dans des paliers fixes dont la distance est égale à au moins quatre fois le diamètre du tube. Si cette solution augmente légèrement la masse des équipages mobiles, elle a en contre-partie l'intérêt d'éviter tout coussinet, garniture et arrivée d'huile mobile et de permettre de rendre les équipages mobiles sensiblement symétriques par rapport à l'axe longitudinal de la machine.The sleepers must be provided with guide means. A first solution consists in providing them with bearings sliding on fixed guide tubes. However, for a high-power installation, it is more advantageous to constitute the guide means by one or more tube (s) fixed (s) to the cross member and moving in fixed bearings the distance of which is equal to at least four times the diameter of the tube. If this solution slightly increases the mass of the moving parts, it has the advantage of avoiding any bearing, lining and arrival of moving oil and making it possible to make the moving parts substantially symmetrical with respect to the longitudinal axis of the machine.

L'invention sera mieux comprise à la lecture de la description qui suit d'une machine multi-tandem qui en constitue un mode particulier de réalisation donné à titre d'exemple non limitatif. La description se réfère aux dessins qui l'accompagnent, dans lesquels:

  • - la fig. 1 est une vue en élévation de la partie gauche de la machine,
  • - la fig. 2 est un schéma de principe montrant la disposition des axes des cylindres moteurs et des cylindres compresseurs de la machine de la fig. 1, vue en bout,
  • - les fig. 3, 4 et 5 sont des vues en coupe suivant les lignes III-III, IV-IV, et V-V de la fig. 1.
The invention will be better understood on reading the following description of a multi-tandem machine which constitutes a particular embodiment given by way of nonlimiting example. The description refers to the accompanying drawings, in which:
  • - fig. 1 is an elevation view of the left part of the machine,
  • - fig. 2 is a block diagram showing the arrangement of the axes of the driving cylinders and the compression cylinders of the machine of FIG. 1, end view,
  • - figs. 3, 4 and 5 are sectional views along lines III-III, IV-IV, and VV of FIG. 1.

La machine montrée en fig. 1 comporte un bâti, un équipage mobile interne et un équipage mobile externe, ainsi que des conduites fixes de circulation des gaz.The machine shown in fig. 1 comprises a frame, an internal mobile assembly and an external mobile assembly, as well as fixed gas circulation pipes.

Le bâti comporte un socle 10 et un sommier supérieur 11 sensiblement de même longueur, reliés par une structure monobloc interne 12 et deux cadres 13, symétriquement disposés par rapport au plan médian III. Cette constitution, complétée par des structures cruciformes 14, donne au bâti une très grande rigidité.The frame comprises a base 10 and an upper base 11 substantially of the same length, connected by an internal monobloc structure 12 and two frames 13, symmetrically arranged with respect to the median plane III. This constitution, supplemented by cruciform structures 14, gives the frame very great rigidity.

Le bâti porte, par des moyens qui seront décrits plus loin, quatre cylindres moteurs, dont deux, 15a et 15b, apparaissent sur la fig. 1, de chaque côté du plan médian III. Les axes des quatre cylindres 15a, 15b, 15c et 15d sont disposés aux angles d'un rectangle 16 qui, dans le mode de réalisation illustré, est disposé avec son grand côté verticalement. Deux cylindres compresseurs internes à double effet 17a et 17b sont montés un de chaque côté de la structure monobloc centrale 12. Les axes de ces cylindres 17a et 17b intersectent la petite médiane 18 du rectangle 16. A chaque cadre 13 sont fixés deux cylindres compresseurs 18a et 18b également à double effet. Les axes des cylindres 18a et 18b intersectent la grande médiane 19 du rectangle 16, à l'extérieur de celui-ci.The frame carries, by means which will be described later, four driving cylinders, two of which, 15a and 15b, appear in FIG. 1, on each side of the median plane III. The axes of the four cylinders 15a, 15b, 15c and 15d are arranged at the corners of a rectangle 16 which, in the illustrated embodiment, is arranged with its large side vertically. Two internal double-acting compressor cylinders 17a and 17b are mounted one on each side of the central monobloc structure 12. The axes of these cylinders 17a and 17b intersect the small median 18 of the rectangle 16. To each frame 13 are fixed two compressor cylinders 18a and 18b also double acting. The axes of the cylinders 18a and 18b intersect the large median 19 of the rectangle 16, outside of the latter.

On ne décrira pas ici la structure des collecteurs placés autour des compresseurs et les clapets, étant donné qu'elle peut être l'une de celles déjà connues, par exemple celle décrite dans le brevet US 3669571.The structure of the collectors placed around the compressors and the valves will not be described here, since it can be one of those already known, for example that described in US Pat. No. 3,669,571.

On décrira maintenant successivement la constitution de l'équipage mobile interne et celle de l'équipage mobile externe.We will now describe successively the constitution of the internal mobile equipment and that of the external mobile equipment.

L'équipage mobile interne comprend une traverse centrale 20 (fig. 3) qui, du fait des efforts auxquels elle est soumise, sera généralement usinée dans une pièce forgée unique. La traverse 20 est fixée sur un tube axial 21 de guidage, porté par des paliers (non représentés) écartés l'un de l'autre d'une distance au moins égale à trois fois le diamètre du tube, et fixés au bâti. La traverse comporte deux bras opposés horizontaux fixés aux tiges 29 des pistons des cylindres compresseurs internes 17a et 17b. Deux excroissances de la traverse sont fixées aux tiges des pistons des cylindres moteurs internes 15a, 15b, 15c et 15d.The internal mobile assembly comprises a central cross member 20 (FIG. 3) which, due to the forces to which it is subjected, will generally be machined in a single forged part. The cross member 20 is fixed to an axial guide tube 21, carried by bearings (not shown) spaced from each other by a distance at least equal to three times the diameter of the tube, and fixed to the frame. The cross member has two opposite horizontal arms fixed to the rods 29 of the pistons of the internal compressor cylinders 17a and 17b. Two protrusions of the cross are attached to the rods of the pistons of the internal engine cylinders 15a, 15b, 15c and 15d.

La nécessité d'un graissage des pièces en déplacement relatif conduit à l'apparition d'un brouillard d'huile dans la zone proche de la traverse 20. Suivant l'invention, la structure monobloc centrale permet d'éviter des projections et des dispersions importantes de lubrifiant. Pour cela, on constitue cette structure centrale par une cage 22, à l'intérieur de laquelle est placé un carter 23 enveloppant la travese et de dimensions axiales suffisantes pour autoriser le débattement de celle-ci. Le carter 23 est évidemment muni de joints de passage des tiges 29 reliant la traverse aux pistons. Ce carter ou la cage peuvent porter les paliers du tube de guidage 21.The need for lubrication of the parts in relative movement leads to the appearance of an oil mist in the area near the cross member 20. According to the invention, the central monobloc structure makes it possible to avoid projections and dispersions. important lubricant. For this, this central structure is constituted by a cage 22, inside which is placed a casing 23 enveloping the span and of sufficient axial dimensions to allow the movement thereof. The casing 23 is obviously provided with seals for the passage of the rods 29 connecting the cross-member to the pistons. This casing or the cage can carry the bearings of the guide tube 21.

Grâce à la grande rigidité de la cage 22, il est possible de fixer directement les compresseurs internes 17a et 17b sur la cage, ce qui permet d'avoir une symétrie de révolution des circuits internes améliorée.Thanks to the high rigidity of the cage 22, it is possible to directly fix the internal compressors 17a and 17b on the cage, which allows an improved symmetry of revolution of the internal circuits.

L'équipage mobile externe présente une constitution symétrique par rapport au plan médian III. Il comporte deux traverses externes 24 (fig. 4) dont l'envergure peut être rendue très inférieure à celle de la traverse centrale 20, ce qui offre plusieurs avantages. D'une part, on tend à équilibrer les masses des équipages internes et externes de façon inhérente. D'autre part, les contraintes subies par les traverses externes sont sensiblement diminuées, particulièrement au cours de la phase motrice, lorsque des efforts de signes opposés sont transmis par les tiges des pistons moteurs externes 25a, 25b, 25c et 25d et les tirants 26a et 26b de liaison entre les traverses 24, placés au droit des tiges des pistons des cylindres compresseurs 18a et 18b. Cette disposition des tirants leur permet de passer en dehors de la traverse centrale 20. Il est en conséquence possible de leur donner une constitution monobloc et d'autoriser un démontage relativement aisé de la traverse 20.The external mobile assembly has a symmetrical constitution with respect to the median plane III. It comprises two external crosspieces 24 (FIG. 4), the span of which can be made much smaller than that of the central crosspiece 20, which offers several advantages. On the one hand, there is a tendency to balance the masses of internal and external crews inherently. On the other hand, the stresses undergone by the external crosspieces are significantly reduced, particularly during the driving phase, when forces of opposite signs are transmitted by the rods of the external driving pistons 25a, 25b, 25c and 25d and the tie rods 26a and 26b of connection between the crosspieces 24, placed in line with the rods of the pistons of the compressor cylinders 18a and 18b. This arrangement of the tie rods allows them to pass outside the central cross member 20. It is consequently possible to give them a one-piece construction and to allow relatively easy disassembly of the cross member 20.

Les traverses 24, comme la traverse 20, sont enfermées dans un carter 27 muni de joints coulissants livrant passage aux tiges de pistons et aux tirants. Elles sont munies de tubes de guidage 28 coulissant dans des paliers non représentés. Ces paliers peuvent être portés par le carter 27 ou par une cage 30 qui l'entoure et renforce le cadre portant les compresseurs.The cross members 24, like the cross member 20, are enclosed in a casing 27 provided with sliding seals providing passage to the piston rods and the tie rods. They are provided with guide tubes 28 sliding in bearings not shown. These bearings can be carried by the casing 27 or by a cage 30 which surrounds it and reinforces the frame carrying the compressors.

La disposition de traverses centrale et externe qui vient d'être décrite présente des avantages importants par rapport à la disposition qui vient la première à l'esprit et qui consiste à aligner les compresseurs internes et externes.The arrangement of central and external sleepers which has just been described has significant advantages over the arrangement which comes first to mind and which consists in aligning the internal and external compressors.

Comme indiqué plus haut, il est nécessaire de prévoir un dispositif de synchronisation des mouvements des équipages. Du fait de la grande différence de rigidité entre les équipages mobiles (l'équipage interne étant monolithique tandis que l'équipage externe est en deux moitiés assemblées par des tirants dont la raideur est forcément faible), le dispositif de synchronisation est sollicité deux fois par cycle par un effort bref mais intense.As indicated above, it is necessary to provide a device for synchronizing the movements of the crews. Due to the great difference in rigidity between the moving parts (the internal part being monolithic while the external part is in two halves assembled by tie rods whose stiffness is necessarily low), the synchronization device is stressed twice by cycle by a brief but intense effort.

Pour absorber cet effort, un accouplement élastique est prévu. Mais une élasticité excessive doit être évitée, car elle fait apparaître des problèmes de vibrations. Par ailleurs, il faut se souvenir que tout dispositif qui fait apparaître des efforts de basculement sur les systèmes de guidage se traduit par des pertes mécaniques par frottements accrus.To absorb this force, an elastic coupling is provided. But excessive elasticity should be avoided, as it causes vibration problems to appear. Furthermore, it should be remembered that any device which shows tilting forces on the guide systems results in mechanical losses by increased friction.

Dans le mode de réalisation illustré de la machine suivant l'invention, ces problèmes sont écartés grâce à un dispositif de synchronisation double qui tend à éviter les dissymétries d'effort.In the illustrated embodiment of the machine according to the invention, these problems are eliminated thanks to a double synchronization device which tends to avoid asymmetries of effort.

Ce dispositif comprend deux roues dentées 31 (fig. 4 et 5) placées dans le plan horizontal médian de la machine. Chaque roue 31 engrène deux crémaillères 32 et 33. Les crémaillères 32 sont fixées à la traverse centrale 20 tandis que les crémaillères 33 sont fixées à une des traverses externes 24. Les deux roues 31 sont placées d'un même côté du plan vertical médian de la machine pour ne pas constituer avec les tirants 26 un système hyperstatique et elles sont montées sur des paliers présentant une élasticité permettant d'absorber les chocs.This device comprises two toothed wheels 31 (fig. 4 and 5) placed in the median horizontal plane of the machine. Each wheel 31 meshes with two racks 32 and 33. The racks 32 are fixed to the central cross member 20 while the racks 33 are fixed to one of the external cross members 24. The two wheels 31 are placed on the same side of the median vertical plane of the machine so as not to constitute with the tie rods 26 a hyperstatic system and they are mounted on bearings having an elasticity making it possible to absorb shocks.

La fixation des différents cylindres est effectuée par des moyens qui limitent les porte-à-faux. Comme indiqué plus haut, les cylindres compresseurs externes 18a et 18b sont fixés par leur face interne, voisine de la traverse. Cette face est fixée par des boulons qui peuvent également servir à retenir les plaques porte-clapet, sur le cadre correspondant 13. Ce cadre, dont la profondeur est voisine de l'épaisseur de la traverse 24, est lui-même fixé entre socle 10 et sommier 11. Il est réduit en son milieu par une structure cruciforme qui sera décrite plus loin.The fixing of the different cylinders is carried out by means which limit the overhangs. As indicated above, the external compressor cylinders 18a and 18b are fixed by their internal face, adjacent to the cross-member. This face is fixed by bolts which can also serve to retain the valve-holder plates, on the corresponding frame 13. This frame, the depth of which is close to the thickness of the cross-member 24, is itself fixed between base 10 and box spring 11. It is reduced in the middle by a cruciform structure which will be described later.

La rigidité de l'ensemble peut être accrue en reliant les fonds des cylindres 18a et 18b par une plaque 34 (fig. 1).The rigidity of the assembly can be increased by connecting the bottoms of the cylinders 18a and 18b by a plate 34 (fig. 1).

Il subsiste dans ce cas un porte-à-faux, mais les efforts correspondants sont négligeables comparés aux efforts dynamiques qui, eux, sont centrés par rapport à la fixation des compresseurs.In this case there remains a cantilever, but the corresponding forces are negligible compared to the dynamic forces which are centered with respect to the fixing of the compressors.

La fixation des cylindres compresseurs internes 17a et 17b pose un problème que l'on ne trouve pas dans le cas des cylindres compresseurs externes 18a et 18b. En effet, il faut que l'accès aux injecteurs des moteurs soit possible et qu'on puisse démonter les cylindres moteurs sans travaux préalables importants et de préférence en bloc.The fixing of the internal compressor cylinders 17a and 17b poses a problem which is not found in the case of the external compressor cylinders 18a and 18b. Indeed, it is necessary that the access to the injectors of the engines is possible and that one can disassemble the engine cylinders without important preliminary works and preferably in block.

Ce résultat est atteint grâce à la présence de la structure monobloc interne 12. Les cylindres compresseurs 17a et 17b sont fixés par brides sur des parties latérales de la cage 22, prévue à cet effet en tôle de forte épaisseur (40 mm par exemple).This result is achieved thanks to the presence of the internal monobloc structure 12. The compressor cylinders 17a and 17b are fixed by flanges on lateral parts of the cage 22, provided for this purpose in very thick sheet metal (40 mm for example).

Grâce à cette disposition, les cylindres compresseurs peuvent avoir une véritable symétrie de révolution en ce qui concerne les circuits d'eau de réfrigération et l'enveloppe d'air comprimé qu'ils refoulent, ce qui est très favorable à la diminution des contraintes thermiques.Thanks to this arrangement, the compressor cylinders can have a true symmetry of revolution with regard to the cooling water circuits and the envelope of compressed air which they discharge, which is very favorable for the reduction of thermal stresses. .

Enfin, les cylindres moteurs 15a à 15d se placent chacun dans un des dièdres de la structure cruciforme 14. Ils peuvent être introduits par simple translation et rotation dans le plan horizontal. Ils sont ainsi introduits dans leur culotte de balayage, préalablement fixée à la structure monobloc. On prévoira avantageusement, autour de l'enveloppe d'eau de l'anneau central de chaque cylindre moteur, un berceau facilitant la fixation.Finally, the driving cylinders 15a to 15d are each placed in one of the dihedrons of the cruciform structure 14. They can be introduced by simple translation and rotation in the horizontal plane. They are thus introduced into their sweeping pants, previously fixed to the one-piece structure. Advantageously, a cradle facilitating fixing is provided around the water envelope of the central ring of each engine cylinder.

Les dispositions mécaniques qui viennent d'être décrites permettent d'arriver à des circuits de fluides particulièrement avantageux et permettant d'utiliser des cycles thermodynamiques complexes, favorables à un rendement élevé.The mechanical arrangements which have just been described make it possible to arrive at particularly advantageous fluid circuits and making it possible to use complex thermodynamic cycles, favorable to high efficiency.

On notera tout d'abord que la présence de carters 23 et 27 permet de recueillir l'huile de graissage des coussinets, donc de diminuer les pertes et la contamination par l'huile. L'huile est recueillie dans le fond des carters 23 et 27 et elle est évacuée par des purgeurs automatiques avant d'être remélangée aux excédents d'huile des cylindres moteurs. De telles sorties d'huile 35 et 36 apparaissent sur les fig. 3 et 4.It should first of all be noted that the presence of casings 23 and 27 makes it possible to collect the lubricating oil from the bearings, therefore to reduce losses and contamination by the oil. The oil is collected in the bottom of the casings 23 and 27 and it is evacuated by automatic bleeders before being mixed again with the excess oil from the engine cylinders. Such oil outlets 35 and 36 appear in FIGS. 3 and 4.

La circulation d'eau de refroidissement des pistons moteurs s'effectuera par l'intérieur des tiges de pistons et des conduites portées par les traverses. On voit apparaître sur la fig. 3 les conduites 37 d'amenée d'eau traitée de refroidissement des pistons et 38 de retour d'eau. On retrouve également, sur la fig. 4, des conduites d'amenée 40 et de retour 41 d'eau de refroidissement des pistons moteurs externes.The circulation of cooling water for the engine pistons will be carried out from the inside of the piston rods and from the lines carried by the sleepers. We see appear in fig. 3 the pipes 37 for supplying treated water for cooling the pistons and 38 for returning the water. We also find, in fig. 4, supply and return pipes 41 for cooling water from the external engine pistons.

La constitution qui vient d'être décrite se prête parfaitement à la mise en oeuvre d'un double cycle avec suralimentation par turbo-soufflantes, par exemple suivant le schéma décrit dans la demande de brevet français n° 7822168. Cette disposition utilise le fait que l'air comprimé directement dirigé vers la turbine à gaz de détente, additionné à l'air nécessaire pour l'entraînement d'une turbo-soufflante, peut constituer approximativement la moitié du débit fourni par les compresseurs. Elle utilise également le fait que, pour augmenter le rendement, il est avantageux de produire cet air à la pression de marche des moteurs, ce qui permet de gagner, pour l'air directement admis dans la turbine de détente, la perte de charge moteur. On peut notamment utiliser une disposition comportant quatre compresseurs haute pression et quatre compresseurs basse pression.The constitution which has just been described lends itself perfectly to the implementation of a double cycle with supercharging by turbo-blowers, for example according to the diagram described in French patent application n ° 7822168. This provision uses the fact that the compressed air directly directed to the expansion gas turbine, added to the air necessary for driving a turbo-blower, can constitute approximately half of the flow supplied by the compressors. It also uses the fact that, to increase the efficiency, it is advantageous to produce this air at the operating pressure of the engines, which makes it possible to gain, for the air directly admitted into the expansion turbine, the engine pressure drop . One can in particular use an arrangement comprising four high pressure compressors and four low pressure compressors.

Ce résultat est atteint en conservant une répartition simple des collecteurs en regroupant les compresseurs de même type quatre par quatre à chaque extrémité de la machine: les compresseurs 17a, 17b, 18a, 18b, placés à gauche du plan médian, constituent un premier groupe, qu'on peut considérer comme étant à haute pression (HP); les quatre compresseurs situés de l'autre côté peuvent être considérés comme à moyenne pression (MP).This result is achieved by keeping a simple distribution of the collectors by grouping compressors of the same type four by four at each end of the machine: the compressors 17a, 17b, 18a, 18b, placed to the left of the median plane, constitute a first group, which can be considered to be high pressure (HP); the four compressors on the other side can be considered as medium pressure (MP).

Tous les cylindres compresseurs aspirent de l'air à partir des caissons constitués par la cage 22 et les cadres 13, caissons alimentés en air par une turbo-soufflante non représentée.All the compressor cylinders suck in air from the boxes formed by the cage 22 and the frames 13, boxes supplied with air by a turbo-blower not shown.

Les compresseurs 18a, 18b, 17a et 17b placés à gauche du plan médian, c'est-à-dire les compresseurs HP, débitent dans des collecteurs HP 43 par des brides 44 décalées par rapport à l'axe (fig.1 1 et 3). Les collecteurs 43 sont munis de réfrigérants 45 (fig. 1 ) et débitent dans des collecteurs de balayage 46 qui alimentent à leur tour tous les cylindres moteurs 15a-d.The compressors 18a, 18b, 17a and 17b placed to the left of the median plane, that is to say the HP compressors, flow into HP collectors 43 by flanges 44 offset from the axis (fig. 1 1 and 3). The collectors 43 are provided with refrigerants 45 (FIG. 1) and flow into sweep collectors 46 which in turn supply all the engine cylinders 15a-d.

Les cylindres compresseurs MP, placés à droite du plan médian, alimentent un collecteur moyenne pression (non représenté sur la figure). Une fraction de l'air admis dans ce collecteur MP est envoyée à une turbine à air d'entraînement de la turbo-soufflante. Le reste de l'air est mélangé aux gaz d'échappement provenant des cylindres moteurs 15a-d et alimente une turbine à gaz attelée à la charge, constituée par exemple par un alternateur.The MP compressor cylinders, placed to the right of the median plane, supply a medium pressure manifold (not shown in the figure). A fraction of the air admitted to this manifold MP is sent to an air turbine driving the turbo-blower. The rest of the air is mixed with the exhaust gases coming from the engine cylinders 15a-d and feeds a gas turbine coupled to the load, constituted for example by an alternator.

Claims (10)

1. Multi-tandem free piston machine, comprising a mounting, an inner movable mechanism comprising a central cross-member (20) transverse to an axis of the mounting, guided in translation so as to be movable with an alternating motion along said axis, bearing, on each side, four inner drive pistons movable along drive cylinders (15a-15d) arranged at the corners of a rectangle and two compressor pistons sliding in inner compressor cylinders (17a, 17b) whose axes pass outside said rectangle, an outer movable mechanism comprising two outer cross-members (24) connected by at least one tie-rod (26a, 26b), each bearing four outer drive pistons movable in four of said drive cylinders and two compressor pistons sliding in outer compressor cylinders (18a, 18b) and means for synchronizing the alternating movement of the two mechanisms, wherein the mounting includes a base (10) and an upper header (11) connected by at least one central one-piece structure on which the inner compressor cylinders (17a, 17b) are fixed.
2. Machine according to claim 1, wherein the central structure comprises a caisson (22, 23) constituting a manifold for the intake of air into the inner compressors, on which the compressors are fixed by their terminal face.
3. Machine according to claim 2, wherein the caisson comprises a casing (23) containing the central cross-member and provided with fluid- tight cross-members for the rods (29) of the drive pistons.
4. Machine according to one of claims 1 to 3, comprising two lateral frames (13) on which are fixed at the end the outer compressors (18a, 18b) connected by respective cruciform structures (14) to the central one-piece structure.
5. Machine according to claim 4, wherein each of the drive cylinders (15a-15d) is fixed in one of the dihedral angles of the cruciform structure.
6. Machine according to claim 1 or 2, wherein the outer compressor pistons are connected by tie-rods (26a, 26b) passing outside of the central cross-member (20).
7. Machine according to claim 1, wherein each frame (13) constitutes, with the base, the header and a casing (27) which it contains and which defines a space containing the corresponding outer cross-member, a supply manifold for the outer compressor cylinders.
8. Machine according to claim 7, wherein the outer cross-members are guided by two tie-rods (26a, 26b) positioned in the plane of the axes of the outer compressors, in line with the axes of these compressors (18a, 18b).
9. Machine according to claim 7, wherein each cross-member (20 or 24) is provided with guide means constituted by at least one tube fixed to the cross-member and moving in fixed bearings whose distance is equal to at least four times the diameter of the tube.
10. Machine according to claim 9, wherein the synchronizing means for the mechanisms comprise wheels (31) engaging teeth formed on said tubes and transmission racks, and are symmetrical so as to improve the synchronizing efficiency.
EP80901199A 1979-06-25 1981-01-12 Machine with multi tandem free pistons Expired EP0031344B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR7916295 1979-06-25
FR7916295A FR2459875A1 (en) 1979-06-25 1979-06-25 IMPROVEMENTS TO MULTI-TANDEM FREE PISTON MACHINES

Publications (2)

Publication Number Publication Date
EP0031344A1 EP0031344A1 (en) 1981-07-08
EP0031344B1 true EP0031344B1 (en) 1982-12-22

Family

ID=9227056

Family Applications (1)

Application Number Title Priority Date Filing Date
EP80901199A Expired EP0031344B1 (en) 1979-06-25 1981-01-12 Machine with multi tandem free pistons

Country Status (12)

Country Link
US (1) US4678407A (en)
EP (1) EP0031344B1 (en)
JP (1) JPS56500724A (en)
BE (1) BE884002A (en)
CA (1) CA1132458A (en)
DE (1) DE3061420D1 (en)
DK (1) DK80181A (en)
FR (1) FR2459875A1 (en)
IT (1) IT1131350B (en)
NO (1) NO153541C (en)
SU (1) SU948297A3 (en)
WO (1) WO1981000019A1 (en)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4564350A (en) * 1982-06-10 1986-01-14 Thomas R. Vigil Plastic extruder assembly
KR20080025366A (en) * 2005-04-29 2008-03-20 텐딕스 디벨롭먼트, 엘엘씨 Radial impulse engine, pump, and compressor systems, and associated methods of operation
US20100242891A1 (en) * 2008-10-30 2010-09-30 Timber Dick Radial impulse engine, pump, and compressor systems, and associated methods of operation
CN101555829B (en) * 2008-11-21 2013-02-20 靳北彪 Free piston load response engine

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3347215A (en) * 1967-10-17 Free piston engines
GB771966A (en) * 1954-07-30 1957-04-10 Hans Petersen Combined free piston internal combustion engine and air compressor assembly
US2812894A (en) * 1955-08-05 1957-11-12 Paul H Schweitzer Tandem engine compressor
US2945618A (en) * 1956-12-15 1960-07-19 Messerschmitt Ag Free-piston compressors
FR1272108A (en) * 1960-08-09 1961-09-22 Engins Pistons Libres Epl Improvements to free piston machines, in particular to auto-compressors or gas generators
FR1601540A (en) * 1968-12-27 1970-08-24
FR2423637A1 (en) * 1978-04-21 1979-11-16 Braun Anton Opposed cylinder reciprocating engine - has rack on one piston and toothed yoke on other to drive same pinions
FR2432089A1 (en) * 1978-07-26 1980-02-22 Benaroya Henry FREE PISTON GENERATOR POWER PLANT

Also Published As

Publication number Publication date
DE3061420D1 (en) 1983-01-27
IT8022859A0 (en) 1980-06-18
EP0031344A1 (en) 1981-07-08
BE884002A (en) 1980-12-29
SU948297A3 (en) 1982-07-30
NO153541B (en) 1985-12-30
US4678407A (en) 1987-07-07
IT1131350B (en) 1986-06-18
NO153541C (en) 1986-04-09
NO810579L (en) 1981-02-19
DK80181A (en) 1981-02-23
JPS56500724A (en) 1981-05-28
FR2459875A1 (en) 1981-01-16
CA1132458A (en) 1982-09-28
WO1981000019A1 (en) 1981-01-08

Similar Documents

Publication Publication Date Title
US7861679B2 (en) Cylinder and piston assemblies for opposed piston engines
US7360511B2 (en) Opposed piston engine
BE1016961A3 (en) IMPROVEMENTS IN THE ENGINE WITH VARIABLE VOLUMETRIC RATIO.
EP0031344B1 (en) Machine with multi tandem free pistons
FR2523700A1 (en) CRYOGENIC COOLING APPARATUS OF SMALL SIZE
FR2491134A1 (en) GAS TURBINE FOR MOTOR VEHICLE
EP2724004A1 (en) Internal combustion engine having a variable transmission
EP0028224B1 (en) Tandem machine with opposite free pistons
FR3014953A1 (en) AIRCRAFT TURBOMACHINE COMPRISING A HEAT EXCHANGER AND A V-GEARBOX
WO1995004877A2 (en) Internal combustion thermal engine comprising at least two opposed cylinders
FR2899645A1 (en) Engine e.g. flat engine, casing for e.g. railway vehicle, has half casings with respective semi-cylinders permitting fixation of sleeves, and recesses in bottom of half casings to permit positioning rolling bearings and/or bearing bush
FR2707710A1 (en) Modular crankshaft for alternative machines.
US20020056430A1 (en) Valve system for OHV-type four-cylinder internal combustion engine
CN108223185B (en) Crankcase and stirling engine for hot-air engine
FR2599084A1 (en) Internal combustion engine without connecting rods or crankshaft of the type having the cylinders in a star formation
FR1364498A (en) Further training in barrel motors
WO2023118730A1 (en) System for cooling a liquid for lubricating an aircraft turbomachine
FR2662468A1 (en) Modular rotary heat engine
WO2008132290A1 (en) Modular crankcase for an engine with opposed cylinders and active chamber
BE342287A (en)
WO2020127295A1 (en) Beta-type stirling machine
EP0048697A1 (en) Plant to convert gas-expansion energy into another form of energy by means of the reciprocating movement of at least one mobile piece
BE418424A (en)
BE405088A (en)
BE513395A (en)

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 19810203

AK Designated contracting states

Designated state(s): CH DE FR GB NL SE

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Designated state(s): CH DE FR GB LI NL SE

REF Corresponds to:

Ref document number: 3061420

Country of ref document: DE

Date of ref document: 19830127

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 19840523

Year of fee payment: 5

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: SE

Payment date: 19840630

Year of fee payment: 5

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 19840822

Year of fee payment: 5

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: CH

Payment date: 19840925

Year of fee payment: 5

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SE

Effective date: 19860624

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: NL

Payment date: 19860630

Year of fee payment: 7

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: NL

Effective date: 19880101

NLV4 Nl: lapsed or anulled due to non-payment of the annual fee
GBPC Gb: european patent ceased through non-payment of renewal fee
PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Effective date: 19881118

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: LI

Effective date: 19890630

Ref country code: CH

Effective date: 19890630

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 19900228

REG Reference to a national code

Ref country code: CH

Ref legal event code: PL

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Effective date: 19900301

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

EUG Se: european patent has lapsed

Ref document number: 80901199.2

Effective date: 19870504

PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT