Two-cylinder pump for heavy flowable materials, such as concrete

Abstract

A two-cylinder pump for heavy flowable materials, such as concrete, comprising a shutter mechanism which is pivotable across an apertured face plate, the shutter mechanism being sealed against the face plate by means of a cutting ring which is axially movable relatively to the shutter mechanism and is supported thereon with its rear side engaging a rectangular-section flexible rubber ring, whereby the cutting ring is urged resiliently against the face plate, means for locating the cutting ring, along a portion of its length, on the shutter mechanism, a seating for the flexible ring on the cutting ring which includes an annular extension which partly overlaps the longer cross-sectional side of the flexible ring in the axial direction, a seating for the flexible ring on the shutter mechanism which includes an annular extension which partly overlaps the longer cross-sectional side of the flexible ring in the axial direction, said annular extensions partly overlapping the ring from opposite sides thereof so that a part of the surface of the ring is left free between the annular extensions, and stops on the cutting ring and the shutter mechanism which limit the extent to which the cutting ring is inserted in said means for locating the cutting ring on the shutter mechanism.

I claim: 
     
       1. A two-cylinder pump for heavy flowable materials, such as concrete, comprising a shutter mechanism which is pivotable across an apertured face plate, the shutter mechanism being sealed against the face plate by means of a cutting ring which has a contact surface on its front end for contacting the face plate and which is axially movable relatively to the shutter mechanism and is supported thereon with its rear end engaging .[.a rectangular cross-section flexible rubber ring, the flexible ring.]. .Iadd.spring means .Iaddend.having first and second sides which are aligned generally axially and first and second ends which are aligned generally radially.[.,.]. .Iadd.with .Iaddend.the first and second sides being of greater length than the first and second ends.[., whereby.]. .Iadd.for urging .Iaddend.the cutting ring .[.is urged.]. resiliently against the face plate, means for locating the cutting ring, along a portion of its length, on the shutter mechanism, one of the shutter mechanism and the cutting ring having a support surface for engaging the first side of the .[.flexible ring.]. .Iadd.spring means .Iaddend.along essentially its entire length, a first seating for the first end of the .[.flexible ring.]. .Iadd.spring means .Iaddend.on the cutting ring which includes an annular extension which partly overlaps the second side of the .[.flexible ring.]. .Iadd.spring means .Iaddend.in the axial direction, a second seating for the second end of the .[.flexible ring.]. .Iadd.spring means .Iaddend.on the shutter mechanism which includes an annular extension which partly overlaps the second side of the .[.flexible ring.]. .Iadd.spring means .Iaddend.in the axial direction, said annular extensions partly overlapping the second side of the .[.flexible ring.]. .Iadd.spring means .Iaddend.from opposite ends thereof so that a part of the second side surface of the .[.flexible ring.]. .Iadd.spring means .Iaddend.is left free between the annular extensions, and stops on the cutting ring and the shutter mechanism which limit the extent to which the cutting ring is inserted in said means for locating the cutting ring of the shutter mechanism. 
     
     
       2. A pump according to claim 1, wherein the means for locating the cutting ring on the shutter mechanism and the annular extension on the shutter mechanism are arranged on the outer side of the shutter mechanism and the shutter mechanism and cutting ring are provided with annular faces which are subjected to hydrostatic pressure for urging the cutting ring on to the face plate and which also serve as stop faces. 
     
     
       3. A pump according to claim 1, wherein the means for locating the cutting ring on the shutter mechanism is arranged on an inner side of the shutter mechanism, the free part of the second side surface of the .[.flexible ring.]. .Iadd.spring means .Iaddend.is subjected to the hydrostatic pressure of the flowable material, and the stops are provided by facing radial surfaces of the cutting ring and shutter mechanism respectively. 
     
     
       4. A pump according to claim 1, wherein the cutting ring has a cylindrical inner surface. 
     
     
       5. A pump according to claim 1, wherein the cutting ring has a conical inner surface, diverging towards the face plate, which is subjected to the hydrostatic pressure of the flowable material. 
     
     
       6. A pump according to claim 1, wherein the seating for the .[.flexible rubber ring.]. .Iadd.spring means .Iaddend.on the cutting ring is disposed opposite and radially outwardly of the seating on the shutter mechanism. 
     
     
       7. A pump according to claim 1, wherein the means for locating the cutting ring on the shutter mechanism includes a cylindrical outer surface of the cutting ring and a cylindrical inner surface of the shutter mechanism which engages the outer cylindrical surface of the cutting ring. 
     
     
       8. A pump according to claim 7, wherein the shutter mechanism includes an annular flange which extends forward from the shutter mechanism toward the face plate, wherein the cylindrical inner surface of the support mechanism forms a portion of an inner surface of the annular flange, and wherein the support surface for engaging the first side of the .[.flexible ring.]. .Iadd.spring means .Iaddend.along essentially its entire length forms a portion of the inner surface of the annular flange. 
     
     
       9. A pump according to claim 8, wherein the stop on the shutter mechanism is a radial surface at a forward end of the annular flange, and wherein the stop on the cutting ring is a radial stop surface which extends outward from the outer cylindrical surface of the cutting ring. 
     
     
       10. A pump according to claim 8, wherein the first seating for the first end of the flexible ring.]. .Iadd.spring means .Iaddend.is defined by an outer surface of the annular extension of the cutting ring, a radial shoulder surface of the cutting ring which engages the first end surface of the .[.flexible ring.]. .Iadd.spring means.Iaddend., and the inner surface of the annular flange of the shutter mechanism.[.;.]..Iadd., .Iaddend.and wherein the second seating is defined by an outer surface of the annular extension of the shutter mechanism, the inner surface of the annular flange of the shutter mechanism, and a radial shoulder surface which engages the second end surface of the .[.flexible ring.]. .Iadd.spring means.Iaddend.. 
     
     
       11. A two-cylinder pump for heavy flowable materials, such as concrete, comprising a shutter mechanism which is pivotable across an apertured face plate, the shutter mechanism being sealed against the face plate by means of a cutting ring which is axially movable relatively to the shutter mechanism and is supported thereon with its rear side engaging .[.a rectangular cross-section flexible rubber ring which has first and second sides and first and second ends, the side being of greater length than the ends whereby the cutting ring is urged.]. .Iadd.spring means having first and second sides which are aligned generally axially and first and second ends which are aligned generally radially with the sides being of greater length than the ends for urging the cutting ring .Iaddend.resiliently against the face plate; a first cylindrical surface associated with the cutting ring and a second cylindrical surface associated with the shutter mechanism for locating the cutting ring, along a portion of its length, on the shutter mechanism; a support surface for engaging the first side of the .[.flexible ring.]. .Iadd.spring means.Iaddend.; a first seating for the first end of the .[.flexible ring.]. .Iadd.spring means .Iaddend.on the cutting ring which includes an annular extension which partly overlaps the second side of the .[.flexible ring.]. .Iadd.spring means .Iaddend.in the axial direction, a second seating for the second end of the .[.flexible ring.]. .Iadd.spring means .Iaddend.on the shutter mechanism which includes an annular extension which partly overlaps the second side of the .[.flexible ring.]. .Iadd.spring means .Iaddend.in the axial direction, said annular extensions partly overlapping the second side of the .[.flexible ring.]. .Iadd.spring means .Iaddend.from opposite ends thereof so that a part of the second side surface of the .[.flexible ring.]. .Iadd.spring means .Iaddend.is left free between the annular extensions, and stops on the cutting ring and the shutter mechanism which limit the extent of axial movement of the cutting ring in a direction away from the face plate. 
     
     
       12. A pump according to claim 11, wherein the first cylindrical surface is a cylindrical outer surface of the cutting ring and the second cylindrical surface is a cylindrical inner surface which engages the outer cylindrical surface of the cutting ring. 
     
     
       13. A pump according to claim 12, wherein the shutter mechanism includes an annular flange which extends forward from the shutter mechanism toward the face plate, wherein the cylindrical inner surface forms a portion of an inner surface of the annular flange, and wherein the support surface for engaging the first side of the .[.flexible ring.]. .Iadd.spring means .Iaddend.forms a portion of the inner surface of the annular flange. 
     
     
       14. A pump according to claim 13, wherein the stop on the shutter mechanism is a radial surface at a forward end of the annular flange, and wherein the stop on the cutting ring is a radial stop surface which extends outward from the outer cylindrical surface of the cutting ring. 
     
     
       15. A pump according to claim 13, wherein the first seating for the first end of the .[.flexible ring.]. .Iadd.spring means .Iaddend.is defined by an outer surface of the annular extension of the cutting ring, a radial shoulder surface of the cutting ring which engages .Iadd.a radial end surface of .Iaddend.the first end .[.surface.]. of the .[.flexible ring.]. .Iadd.spring means.Iaddend., and the inner surface of the annular flange of the shutter mechanism, and wherein the second seating is defined by an outer surface of the annular extension of the shutter mechanism, the inner surface of the annular flange of the shutter mechanism, and a radial shoulder .[.which.]. surface .Iadd.which .Iaddend.engages .Iadd.a radial end surface of .Iaddend.the second end .[.surface.]. of the .[.flexible ring.]. .Iadd.spring means.Iaddend.. 
     
     
       16. A two-cylinder pump for heavy flowable materials, such as concrete, the pump comprising: an apertured face plate;   a shutter mechanism which is pivotable across the apertured face plate, the shutter mechanism having a forward end spaced from and facing the face plate, a first annular flange which extends from the forward end axially toward the face plate, a second annular flange which extends .[.radially.]. .Iadd.axially .Iaddend.from the forward end toward the face plate and which is generally parallel to the first annular flange, a generally radial shoulder surface between the first and second annular flanges, the first and second annular flanges and the radial shoulder surface defining an annular groove, a generally axial support surface associated with the first annular flange, and a generally radial stop surface;   a cutting ring having a contact surface at a front end for contacting the face plate, a generally radial shoulder surface and an annular flange at a rear end, and a generally radial stop surface for engaging the stop surface of the shutter mechanism to limit axial movement of the cutting ring with respect to the shutter mechanism in an axial direction away from the face plate;   .[.a long stroke spring in the form of a flexible ring having a rectangular cross-section.]. .Iadd.spring means .Iaddend.with first and second sides which are aligned generally axially and first and second ends which are aligned generally radially.[., the flexible ring being.]. positioned between the shutter mechanism and the cutting ring for urging the contact surface of the cutting ring resiliently against the face plate, the first side of the .[.flexible ring.]. .Iadd.spring means .Iaddend.engaging the support surface of the shutter mechanism along essentially an entire length of the first side, the first end of the .[.flexible ring.]. .Iadd.spring means .Iaddend.being positioned in a first seating defined by the support surface of the shutter mechanism and the shoulder surface and the annular flange of the cutting ring so that the annular flange of the cutting ring partly overlaps the second side of the .[.flexible ring.]. .Iadd.spring means .Iaddend.in the axial direction, and the second end of the .[.flexible ring.]. .Iadd.spring means .Iaddend.being positioned in a second seating formed by the annular groove in the shutter mechanism so that the second flange of the shutter mechanism partly overlaps the second side of the .[.flexible ring.]. .Iadd.spring means .Iaddend.in the axial direction, the annular flange of the cutting ring and the second annular flange of the shutter mechanism being spaced from one another in the axial direction so that a part of the second side of the .[.flexible ring.]. .Iadd.spring means .Iaddend.is left free between the annular flange of the cutting ring and the second annular flange of the shutter mechanism.   
     
     
       17. A pump according to claim 16, wherein the cutting ring has a cylindrical outer surface, and wherein the first annular flange of the shutter mechanism has a cylindrical inner surface which engages the outer cylindrical surface of the cutting ring. 
     
     
       18. A pump according to claim 17, wherein the support surface forms a part of the inner surface of the first annular flange. 
     
     
       19. A pump according to claim 16, wherein the stop .Iadd.surface .Iaddend.on the shutter mechanism is a radial surface at a forward end of the first annular flange. .Iadd. 
     
     
       20.  The pump of claim 1 wherein the spring means is a rectangular cross-section flexible rubber ring. .Iaddend. .Iadd.21. The pump of claim 11 wherein the spring means is a rectangular cross-section flexible rubber ring. .Iaddend. .Iadd.22. The pump of claim 16 wherein the spring means is a long stroke spring in the form of a flexible ring having a rectangular cross-section. .Iaddend. .Iadd.23. A two cylinder pump for heavy materials which has an apertured face plate, a shutter mechanism pivotable across the face plate, a cutting ring for sealing the shutter mechanism against the face plate with the cutting ring having a contact surface on its front end for contacting the face plate and being axially movable relative to the shutter mechanism, spring means for urging the contact surface of the cutting ring toward the face plate, first means for retaining one end of the spring means in operable engagement with the cutting ring, and second means for retaining an other end of the spring means in operable engagement with the shutter mechanism, characterized in that the spring means has first and second sides which are aligned generally axially and first and second ends which are aligned generally radially with the sides being longer than the ends, the spring means being positioned between the shutter mechanism and the cutting ring with the first side of the spring means engaging a generally axial support surface on the shutter mechanism along essentially an entire length of the first side and the first end of the spring means first being positioned in a first seating defined by the first retaining means which includes an annular extension which partly overlaps the second side of the spring means in the axial direction, and the second end of the spring means being positioned in a second seating defined by the second retaining means which includes an annular extension which partly overlaps the second side of the spring means in the axial direction so that a part of the second side of the spring means is left free between the annular extensions of the first and second retaining means. .Iaddend. .Iadd.24. The pump of claim 23 wherein the cutting ring has a cylindrical inner surface. .Iaddend. .Iadd.25. The pump of claim 23 wherein the shutter mechanism includes an annular flange which extends forward from the shutter mechanism toward the face plate, and wherein the inner surface of the annular flange forms the support surface for engaging the first side of the spring means. .Iaddend. .Iadd.26. The pump of claim 25 wherein the cutting ring has a cylindrical outer surface, and wherein the annular flange on the shutter mechanism includes a cylindrical inner surface which engages the cylindrical outer surface of the cutting ring. 
     
     
        .Iaddend. .Iadd.27.  The pump of claim 25 wherein the first retaining means is defined by an outer surface of the annular extension of the cutting ring, a radial shoulder surface of the cutting ring which engages a radial end surface of the first end of the spring means, and the inner surface of the annular flange of the shutter mechanism, and wherein the second retaining means is defined by an outer surface of the annular extension of the shutter mechanism, the inner surface of the annular flange of the shutter mechanism, and a radial shoulder surface of the shutter mechanism which engages a radial end surface of the second end of the spring means. .Iaddend. .Iadd.28. The pump of claim 23 wherein the shutter mechanism includes an annular flange which extends forward from the shutter mechanism toward the face plate, wherein the stop on the shutter mechanism is a radial surface at a forward end of the annular flange of the shutter mechanism, wherein the cutting ring has a cylindrical outer surface, and wherein the stop on the cutting ring is a radial stop surface which extends outward from the cylindrical outer surface of the cutting ring. .Iaddend. .Iadd.29. The pump of claim 23 wherein the spring means is a generally rectangular cross-section flexible ring. .Iaddend. .Iadd.30. The pump of claim 23 wherein the cutting ring and shutter mechanism have opposed stops aligned for engagement to limit the extent of axial movement of the cutting ring with respect to the shutter mechanism in a direction away from the face plate. .Iaddend. 
     
     
        .Iadd.1.  A two cylinder pump for heavy materials which has an apertured face plate, a shutter mechanism pivotable across the face plate which has an annular flange having an inner cylindrical surface thereon and a radial surface at a forward end of the annular flange, an annular cutting ring for sealing the shutter mechanism against the face plate with the cutting ring having a contact surface on its front end for contacting the face plate, an inner cylindrical surface of generally the same diameter as each aperture in the face plate, and being axially movable relative to the shutter mechanism, axially extending spring means for urging the contact surface of the cutting ring toward the face plate with the spring means having first and second sides which are generally axially aligned and first and second ends which are generally radially aligned, first means for retaining one end of the spring means in operable engagement with the cutting ring, and second means for retaining an other end of the spring means in operable engagement with the shutter mechanism, characterized in that the cutting ring has an annular extension on a rear end thereof which bears an outer cylindrical surface thereon that partly overlaps an inner annular side of the spring means in the axial direction, a radial shoulder surface which engages a radial end surface of one end of the spring means, an outer cylindrical surface which engages the inner cylindrical surface of the annular flange of the shutter mechanism, and a radial stop surface which extends outward from the outer cylindrical surface of the cutting ring for engagement with the radial surface on the annular flange of the shutter mechanism to limit the extent of axial movement of the cutting ring with respect to the shutter mechanism in a direction away from the face plate. .Iaddend. .Iadd.32. A two cylinder pump for heavy materials which has an apertured face plate, a shutter mechanism pivotable across the face plate which has an annular flange having a radial surface at a forward end thereof, a cutting ring for sealing the shutter mechanism against the face plate with the cutting ring being axially movable relative to the shutter mechanism, spring means for urging the cutting ring away from the shutter mechanism, first means for retaining one end of the spring means in operable engagement with the cutting ring, and second means for retaining an other end of the spring means in operable engagement with the shutter mechanism, characterized in that the cutting ring has a contact surface at a front end thereof for contacting the face place, a generally radial shoulder surface and an annular extension at a rear end thereof, and a generally radial stop surface for engagement with the radial surface of the annular flange of the shutter mechanism to limit axial movement of the cutting ring with respect to the shutter mechanism in an axial direction away from the face plate, and the spring means has first and second sides which are aligned generally axially and first and second ends which are aligned generally radially with the sides being longer than the ends, the spring means being positioned between the shutter mechanism and the cutting ring with the first side of the spring means engaging a generally axial support surface on the shutter mechanism along essentially an entire length of the first side and the first end of the spring means first being positioned in a first seating defined by the retaining means which includes the annular extension of the cutting ring which partly overlaps the second side of the spring means in the axial direction, and the second end of the spring means being positioned in a second seating defined by the second retaining means which includes an annular extension which partly overlaps the second side of the spring means in the axial direction so that a part of the second side of the spring means is left free between the annular extensions of the first and second retaining means. .Iaddend.