JP2014206158A - Reciprocation-type positive-displacement pump comprising elastic squeeze pumping member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reciprocation-type positive-displacement pump comprising an elastic squeeze pumping member, which is stabilized under negative pressure and which can also apply a load by great pressure.SOLUTION: An elastic intermediate area 6 between an outside or edge-side sandwich-attachment part 5 and an inside rigid member 3 has a thickness h1 equivalent to at least 0.3 times the minimum free width a between mutually-opposed edges of the rigid member 3 and a sandwich-attachment and support member 7 radially adjoining the rigid member 3.

Description

  The present invention includes an elastic pumping member, an inner rigid drive member or hard member acting at the center of the pumping member, and an elastic member disposed further radially outward with respect to the action portion of the drive member. The present invention relates to a reciprocating positive displacement pump provided with an intermediate region and an edge-side or outer clamping portion for an elastic pumping member.

  Such a positive displacement pump is known as a diaphragm pump for pumping gas and liquid, for example, based on DE 102010009670. In this known positive displacement pump, a pumping member generally formed as a working diaphragm is moved up and down by, for example, an electric motor and an eccentric drive device. Such pumps are used, for example, one for generating a vacuum and the other for pumping a gas or liquid at a relatively low pressure.

  The pumping member or diaphragm typically includes a hard member (steel member) in the center region. The rigid member is acted on by a connecting rod or another elevating drive device, for example, a linear solenoid for elevating motion. Further, the hard member stabilizes the center of the pressure feeding member. The diaphragm is fastened in a state of being sandwiched between the two housing members at the outer edge, that is, is sandwiched and seals the working chamber. Between the two housing members, a substantially annular movable region of a pressure feeding member or a diaphragm is provided. This movable region can partly move up and down by elastic deformation, and can bridge the central region and the outer edge of the pumping member, and the other is in the working chamber. Withstand pressure load. Usually, the material of the pressure feeding member is subjected to tensile / bending stress in relation to the operating pressure in the movable region. That is, the maximum possible operating pressure is limited by the load carrying capacity of the diaphragm material in the movable region.

  In the pinching or clamping part outside the diaphragm, the diaphragm must be clamped in part for sealing, and in order to prevent the tensile and bending stress from causing slippage. Must be fixed in position. This positioning is difficult, especially when coated with PTFE, due to the small coefficient of sliding friction of this material. However, this material is advantageous because of its chemical resistance. Furthermore, additional bending stresses in the material, kinking and, in some cases, slipping occur in the region of the transition section having a predetermined radius of curvature provided between the clamping region and the movable region. This causes material wear, cracks and premature failure.

  A diaphragm for a diaphragm pump is known on the basis of German Patent No. 2713599. This known diaphragm is formed into a corrugated shape extending from the inside to the outside, particularly in an elastic middle region, so that the diaphragm material does not need to be stretched during up and down displacement. Thereby, the lifetime can be increased, and the diaphragm can be moved more easily. However, this diaphragm geometry is only suitable for generating negative pressure. Such a diaphragm is not stable when the positive pressure is low, and is displaced or buckled in the wave region, thereby reducing the pumping performance of the pump.

  In a diaphragm having a flat diaphragm or a thin movable zone, on the one hand, a transition region from the movable zone to a pinched portion on the outer periphery, and on the other hand, a transition region to a hard member provided at the center. It is actually known that a large local bending stress occurs. This bending stress leads to crack formation and a reduction in diaphragm life.

  German Patent No. 10227193 describes that additional bending stresses and elongation occur in the movable region of the diaphragm that is reversed by each reciprocating motion. This bending stress and elongation particularly damages the PTFE layer. This limits the lifetime of the diaphragm. In order to solve this problem, the cited specification proposes a plurality of protrusions provided on the surface, however this does not overload the material even at higher fluid pressures. Nevertheless, no solution is shown how an elastic pumping member or diaphragm must be formed in order to achieve a long lifetime. Even if the protrusion is used, in the region of the reversal portion, a large bending stress and an additional large tensile stress based on the fluid pressure are generated in the diaphragm material. In this case, it is also disadvantageous that the projecting structure increases the clearance volume of the positive displacement pump and thus only achieves the compression that would otherwise be required for suction.

  The reciprocating positive displacement pump allows negative pressure during suction in the working chamber and positive pressure equal to the back pressure applied to the pump outlet line during discharge. There is a problem. One goal is to allow the pump to work against as much back pressure as possible. At that time, it is desirable that the pumping member should not be overloaded, and the pumping performance should remain as constant as possible without being influenced by the back pressure.

German Patent Application Publication No. 102010009670 German Patent No. 2713599 German Patent No. 10227193

  Accordingly, an object of the present invention is to provide a reciprocating positive displacement pump including an elastic pumping member that is not only stable at a negative pressure but also capable of applying a load with a large pressure.

  In order to solve this problem, in the positive displacement pump according to the present invention, the elastic intermediate region between the outer or edge sandwiching portion and the inner hard member has a hard member and a radius to the hard member. It has a thickness of at least 0.3 times the minimum free width between the edges of the sandwiching / supporting members adjacent in the direction facing each other.

  In a preferred embodiment of the positive displacement pump according to the present invention, the elastic intermediate region between the outer edge-side sandwiched portion and the inner hard member has a thickness greater than 0.5 times the minimum free width. Have.

  In a preferred embodiment of the positive displacement pump according to the invention, the inner rigid drive member is connected in a material connection, for example by vulcanization, to an elastic intermediate region or pumping member.

  In a preferred embodiment of the positive displacement pump according to the invention, the axial length of the inner rigid drive member coupled to the elastic part of the pumping member is at least 0.7 times the minimum free width. Dimensioned to size.

  In a preferred embodiment of the positive displacement pump according to the invention, the axial length of the inner rigid drive member coupled to the elastic part of the pumping member is at least 1.5 times the minimum free width. Dimensioned to size.

  In a preferred embodiment of the positive displacement pump according to the present invention, the fluid side surface of the pressure feeding member is formed in a concave shape.

  In a preferred aspect of the positive displacement pump according to the present invention, the concave shape of the pumping member is a concave configuration in which the ratio of the maximum depth to the diameter of the entire concave range is at least 5/100 in a stress-free state. Have a ratio.

  In a preferred embodiment of the positive displacement pump according to the present invention, the displacement amount of the pumping member from the stress-free state is at least 2/3 upward toward the working chamber, and is maximum when facing away from the working chamber. 1/3.

  In a preferred embodiment of the positive displacement pump according to the invention, the height of the rigid drive member coupled to the elastic part has at least 0.5 times the diameter of the rigid drive member.

  In a preferred embodiment of the positive displacement pump according to the present invention, the pumping member has an additional protective layer, and the protective layer is preferably formed thinner than a portion other than the protective layer of the pumping member, It has a higher chemical resistance than an elastic material and is made of, for example, polytetrafluoroethylene.

  In a preferred embodiment of the positive displacement pump according to the invention, the thickness of the elastomer layer up to the protective layer or above the rigid drive member to the surface of the diaphragm or the surface of the pumping member is the maximum diameter of the rigid drive member. The dimension is set to be smaller than 0.15 times.

  In a preferred embodiment of the positive displacement pump according to the present invention, the pressure feeding member has a support portion or a support member on the outer side on the edge side.

  In a preferable aspect of the positive displacement pump according to the present invention, the outer support portion or the support member has an inner diameter smaller than a diameter to which a load is applied by fluid pressure.

  In a preferred embodiment of the positive displacement pump according to the present invention, the elastic middle region is placed on the outer support or support member with a tangential angle smaller than 50 ° in the state of bottom dead center. ing.

  In a preferred embodiment of the positive displacement pump according to the present invention, the outer support portion is provided with a sliding coating layer for minimizing sliding friction, for example made of PTFE or molybdenum disulfide, at least in the region directed to the pumping member. Have.

  In a preferred embodiment of the positive displacement pump according to the invention, the outer support is minimized, for example by addition of PTFE or molybdenum disulfide, together with an elastic intermediate layer material or an elastic pumping member material. It is made of a material having sliding friction.

  In a preferred embodiment of the positive displacement pump according to the present invention, the outer support portion is made of a material having good thermal conductivity, for example, aluminum or an aluminum alloy.

  In a preferred embodiment of the positive displacement pump according to the present invention, the material of the elastic intermediate layer or the material of the elastic pumping member is a vulcanized elastomer or a thermoplastic elastomer such as polyurethane.

  In a preferred embodiment of the positive displacement pump according to the invention, the support member is formed as an outer rigid ring, and the elastic intermediate region of the pumping member is a material on the outer outer rigid ring, in particular material. Connected, for example, by vulcanization.

  In a preferred embodiment of the positive displacement pump according to the present invention, the maximum height of the support member is set to be larger than the thickness of the elastic intermediate region.

  In a preferred embodiment of the positive displacement pump according to the present invention, the layer thickness between the support member and the protective layer is dimensioned to be smaller than 0.15 times the maximum diameter of the rigid drive member, and is elastic. The dimension is set to be smaller than 0.15 times the thickness of a typical intermediate region.

  In a preferred embodiment of the positive displacement pump according to the present invention, the minimum layer thickness between the support member and the protective layer or diaphragm surface is dimensioned less than 0.3 times the thickness of the elastic intermediate region. ing.

  In a preferred embodiment of the positive displacement pump according to the present invention, the connecting rod is provided with another inner support portion for the pressure feeding member, and the elastic support region is provided at least in the working chamber on the other support portion. It is mounted at the maximum displacement of the pumping member in the direction of.

  In a preferred embodiment of the positive displacement pump according to the present invention, the other support portion has an outer diameter that is larger than half the sum of the diameter of the drive member and the inner diameter of the outer support portion, but smaller than the inner diameter of the outer support portion. have.

  In a preferred embodiment of the positive displacement pump according to the present invention, at least the surface of the pumping member on the side opposite to the working chamber has a sliding coating layer for reducing or minimizing sliding friction.

  In order to solve the above-mentioned problems, the reciprocating positive displacement pump provided with an elastic pumping member has an elastic intermediate between the outer or edge-side clamping part and the inner hard member. The region has a thickness of at least 0.3 times the minimum free width between the edges of the rigid member and the clamping / supporting member radially adjacent to the rigid member facing each other; It is characterized by being. As a result, the elastic pumping member or diaphragm geometry is such that the elastomer undergoes little tensile or bending stress, however, the fluid pressure load is transmitted to the hard member or drive member with thrust stress. It is formed. By this means according to the invention, the elastomer is mainly compressed by reciprocating movements, however, hardly stretched. This can extend the life accordingly.

  Another means for improving the lifetime is that the elastic intermediate region between the outer edge clamp and the inner rigid member is at least 0.5 times the minimum free width as defined previously. It may have a thickness. Correspondingly, based on this greater thickness, the load capacity is greater.

  The inner rigid drive member or rigid member may be connected to the elastic intermediate region in a material connection, for example by vulcanization. Correspondingly, it is possible to successfully transmit the force from the drive member to the pumping member.

  The axial length of the inner rigid drive member or rigid member coupled to the elastic portion of the pumping member may be dimensioned to be at least 0.7 times the smallest free width. . This gives a geometric shape with good mobility and high lifetime.

  The axial length of the inner rigid drive member coupled to the elastic portion of the pumping member may be sized to be at least 1.5 times the smallest free width. This strengthens the coupling between the drive member and the pumping member. According to this aspect, the pumping member may have a correspondingly sized recess for coupling with the drive member. The recess covers the drive member by the provided amount and surrounds the drive member for gripping.

  The fluid side surface of the pumping member may be formed in a concave shape. That is, in the rest position, the pumping member is recessed in a concave shape. This depression is included in the pumping chamber of the pump.

  It is preferable that the concave shape of the pumping member has a concave ratio in which the ratio of the maximum depth to the diameter of the entire concave range is at least 5/100 in a state without stress.

  For the sufficient performance of the positive displacement pump and the long life of the elastic pumping member, the displacement of the pumping member from the stress-free state is at least 2/3 toward the working chamber, It is preferable that the maximum is 1/3 in the direction away from the distance. That is, the diaphragm or the pumping member can be displaced by 2/3 upward toward the working chamber with respect to the total displacement, and can be displaced by 1/3 downward in the direction away from the working chamber. And may be displaceable with respect to its dimensions.

  For securing the pumping member and drive member, the height or engagement depth of the rigid drive member coupled to the elastic portion has at least 0.5 times the diameter of the rigid drive member. It is preferable that

  The pumping member has an additional protective layer, which is preferably formed thinner than the portion other than the protective layer of the pumping member, and has higher chemical resistance than the elastic material. For example, polytetrafluoroethylene PTFE.

  For good mobility as well as high life of the pumping member, the thickness of the elastomer layer up to the protective layer or above the diaphragm or the surface of the pumping member to the surface of the diaphragm is determined by the rigid driving member. It is advantageous if the dimensions are set to be smaller than 0.15 times the maximum diameter. That is, in the region of the drive member, the diaphragm or the elastic pumping member can be formed relatively thin. From this region, it is preferable to connect the thicker elastic intermediate region via the arc-shaped region. Can be migrated to.

  For the movement of the elastic pumping member and the limitation of movement, it is particularly preferred and advantageous if the pumping member has a peripheral outer support. At the same time, this outer support portion mainly restricts the elastic intermediate region toward the outside, but it is more than the degree of freedom of movement in the direction away from the pump chamber, particularly during the movement of the pumping member into the pump chamber. A somewhat large degree of freedom of movement is allowed.

  In one refinement, the outer support, which may be formed, for example, as an annular support member, may have an inner diameter that is smaller than the diameter in the pump chamber that is loaded by the fluid pressure. Therefore, especially when a pressure is applied to the pressure-feeding member, the pressure-feeding member is supported even if adjacent to the clamping region.

  Despite good support of the pumping member, for sufficient mobility, the contour of the elastic middle region is tangentially less than 50 ° in the bottom dead center state, ie at maximum displacement. It is preferred that the support part is mounted on the outer support part with a corner, preferably with an arcuate contour.

  The outer support may have a slip coating layer, for example made of PTFE or molybdenum disulfide, for reducing sliding friction.

  In one variant or additional measure, the outer support, together with the elastic intermediate layer material or elastic pumping member material, reduces sliding friction, for example by the addition of PTFE or molybdenum disulfide. It is formed from the material which has.

  The outer support portion may be formed of a material having good thermal conductivity, such as aluminum or an aluminum alloy. Therefore, the support portion can also act as a cooling body, that is, a heat sink.

  The material of the elastic intermediate layer or the material of the elastic pumping member may be a vulcanized elastomer or a thermoplastic elastomer such as polyurethane.

  In a preferred aspect of the positive displacement pump according to the present invention, the support member is formed as a radially outer rigid ring, and the elastic intermediate region of the pumping member is connected to the outer rigid ring on the edge side. In particular, it may be joined in material connection, for example by vulcanization. In this way, in particular, the radially outer edge region of the pumping member obtains a coordinated fixation at all displacement positions, and the relative movement between the support member and the pumping member extending annularly around the outer circumference is avoided. The

  It is preferred that the maximum height of the annular support member is dimensioned larger than the thickness of the elastic intermediate region. The annular support member is reasonably well reached relative to the pumping member and serves to define an elastic intermediate region.

  The layer thickness of the outermost edge region of the pumping member between the support member and the protective layer disposed on the pumping member is dimensioned to be less than 0.15 times the maximum diameter of the rigid drive member. And may be dimensioned less than 0.15 times the thickness of the elastic intermediate region. This indicates the preferred dimensions of the outer edge of the pumping member above the support member, which is clamped or pinched in use. At the same time, the relatively low thickness of the protective layer makes it possible to limit the overall structural height of the positive displacement pump even in this edge region.

  Dimensioning the minimum layer thickness in the edge region of the pumping member between the support member and the protective layer or diaphragm surface, i.e. the surface of the pumping member, is less than 0.3 times the thickness of the elastic intermediate region It is preferable that

  In another preferred embodiment of the positive displacement pump according to the present invention, in addition to the above-described support member, the connecting rod is provided with another support portion on the inside for the pumping member. The elastic intermediate region may be placed on the support portion at least during the maximum displacement of the pumping member in the direction of the working chamber. That is, the other support portion on the inner side is located on the same side of the elastic pumping member as the first annular support member extending over the entire circumference on the outer side in the radial direction. In this case, the pressure applied to the pressure feeding member is introduced into the connecting rod.

  Another support may have an outer diameter that is greater than half the sum of the drive member diameter and the inner diameter of the outer support, but less than the inner diameter of the outer support. Due to such dimensional conditions, the elastic intermediate region not only has a sufficient size, especially when deformed away from the working chamber, but is also relatively less when displaced in the reverse direction according to the invention. It is ensured that there is still a sufficient degree of freedom for deformation. At the same time, during the displacement into the working chamber, good support is achieved even in the elastic middle region of the pumping member.

  An additional means that is also suitable for the efficiency and wear of the pumping member is that at least the surface of the pumping member opposite the working chamber has a sliding coating layer to reduce or minimize sliding friction. You may have. This ensures that the relative frictional motion caused by the inner support during the relative movement of the inner support relative to the lower surface of the pumping member has little or no effect on the direction of wear of the pumping member. It has become. This can also be applied to the case where the outer support member is not connected in material connection to the pumping member and some relative movement occurs when the pumping member is deformed.

  In particular, when the individual or plurality of features and means described above are combined, a pressure-feeding member is provided in which the pressure load is transmitted to the rigid member at the center of the pressure-feeding member, particularly by the thrust load, among the movable regions of the elastic pressure-feeding member A positive displacement pump is obtained. Depending on the size of the thickness, a larger operating pressure can be received while the thrust load on the diaphragm material remains constant. Due to the concave surface, upon upward displacement, the surface or a protective layer disposed on the surface, for example a PTFE layer, is only subjected to pressure loads and is therefore not at risk of tearing. Is the layer thickness above the central drive member or rigid member small and may be set to less than 1.5 mm, for example, so that the “lateral escape” of the rubber or elastomer under pressure load is also reduced? Or it is blocked.

  In the present invention, the elastomer is hardly subjected to the tensile / bending stress, however, the fluid pressure load can be transmitted to the driving member or the hard member with the thrust stress. And rigid member geometric shapes can be formed. The elastomer of the pressure feeding member is mainly compressed by the reciprocating motion and hardly stretched.

It is a longitudinal cross-sectional view which shows the positive displacement pump which concerns on this invention provided with the elastic pumping member in the position where stress was removed. The elastic pumping member region provided with the sandwiching part and the action part of the action member (drive member) provided inside the positive displacement pump and the drive member are arranged at a radial interval. It is an enlarged view which shows a support member in the position from which stress was removed, and in this case, a pumping member has an additional thin protective layer on the upper surface. FIG. 3 is a view corresponding to FIG. 2 showing an embodiment without a protective layer, and in this case, both possible displacements of the pumping member up and down are indicated by two-dot chain lines. It is a figure which shows modified embodiment, In this embodiment, the 2nd support member or support part is provided immediately adjacent to the drive member, and in this case, a pumping member has a protective layer. The position displaced upward is indicated by a two-dot chain line. FIG. 5 is a diagram showing the embodiment shown in FIG. 4 provided with a pumping member displaced upward, in which case the drive member and the second support part are moved upward, as shown in FIG. Unlike the starting position or the lowered position, the support portion is in contact with the pumping member from below.

  In the following, embodiments for carrying out the present invention will be described in detail with reference to the drawings.

  In the following description of different embodiments, the same reference numerals are given to the functionally identical members even when the configuration is changed.

  A reciprocating positive displacement pump having an elastic pumping member 2 or a diaphragm pump having a diaphragm, generally indicated by reference numeral 1, can be moved up and down in a known manner by a connecting rod 4. It has the member 3 or a hard member.

  As a result, the pressure feeding member 2 is moved up and down. This is illustrated in FIG. 3 by two-dot chain lines at different positions, and in FIGS. 4 and 5 at different positions.

  The edge region 5 of the pumping member 2 is sandwiched in a manner known per se in all embodiments. In the elastic pumping member 2, an elastic intermediate region 6 is provided between the clamped edge region 5 and the action portion of the driving member 3. This intermediate region 6 allows different movements of the pumping member 2 up and down and is deformed in that case.

  The elastic intermediate region 6 is located between the outer or edge-side sandwiched portion 5 and the inner drive member 3, and is the minimum between the drive member 3 and the sandwiched portion 5 or the support member 7. Has a transverse thickness greater than 0.3 times the free width of In FIG. 2 and FIG. 4, the free width “a” is shown to stand out. The thickness of the pressure-feeding member 2 is also entered in the same figure and is indicated by the symbol h1.

  In the present embodiment, the thickness h1 is dimensioned even greater than 0.5 times the minimum free width a.

  The rigid drive member or hard member 3 is coupled to the elastic intermediate region 6 and thus to the elastic pumping member 2 by vulcanization in a material connection. A slightly curved hard member 3 is observed. The hard member 3 is disposed on the connecting rod 4 and is surrounded by the elastic pumping member 2 and the elastic intermediate region 6 of the pumping member 2 so as to be sufficiently gripped. Force transmission is possible. Furthermore, the area surrounding the drive member 3 of the pressure-feeding member 2 is supported by the connecting rod 4, whereby the force of this connecting rod 4 is transmitted well to the pressure-feeding member 2, especially in the form of thrust. be able to.

  The axial length h5 of the inner rigid drive member 3 shown in FIG. 2 is dimensioned to about 1.5 times the already mentioned free width a. Thus, even when a dynamic load is applied by the pumping operation, a stable fixing state is achieved.

  According to FIGS. 1 to 4, the surface of the pressure-feeding member 2 on the fluid side facing the working chamber 8 is concave in the stress-removed position of the pressure-feeding member 2 or without any stress being displaced. Molded and recessed. At this time, the deepest portion of the concave depression is disposed above the center of the drive member 3.

  Possible displacement positions of the pumping member 2 can be seen in FIG. 3, and furthermore, it can be seen by comparing FIG. 4 and FIG. The amount of displacement of the pressure-feeding member 2 from the state without stress is about 2/3 of the total displacement upward in the work chamber 8 and about 1/3 of the total displacement downward in the direction away from the work chamber 8. 3. That is, the portion with the larger displacement amount is generated upward in the thrust direction of the drive member 3. As can be seen in FIGS. 2, 4 and 5, the elastic pumping member 2 may have an additional protective layer 9 which is relatively thin. This protective layer 9 has higher chemical resistance than an elastic material other than the protective layer of the pressure feeding member 2, and is made of, for example, polytetrafluoroethylene.

  The elastic material thickness h3 of the elastic pumping member 2 above the rigid drive member 3 or the elastic pumping member 2 as a whole is 0.15 times the diameter D of the rigid drive member 3. Therefore, a relatively small amount of deformation can be expected in the material of the pressure feeding member 2 at this point when the driving member 3 moves.

  In the embodiment shown in FIG. 1 to FIG. 3, a support member 7 extending over the entire circumference is provided in the clamping region 5, and is relatively relative to the curved surface inside the support member 7. In the embodiment shown in FIGS. 4 and 5, the elastic intermediate region 6 of the elastic pumping member 2 can move and is correspondingly supported during the lowering movement. In the vicinity of the hard member 3, adjacent to the hard member 3, another connecting portion 10 is also provided on the connecting rod 4. This support portion 10 additionally supports and stabilizes the pressure feeding member 2 at the upper position shown in FIG.

  Furthermore, the outer support 7 may be made of a material with good thermal conductivity, for example aluminum or an aluminum alloy, thereby acting as a cooling body, ie a heat sink.

  Furthermore, as can be seen in FIG. 3, the elastic pumping member 2, in particular the elastic intermediate region 6 of the elastic pumping member 2, is formed as an outer rigid ring extending around the entire circumference on its outer side during its movement. Although it is partially placed on the support member 7, it is partially lifted from the support member 7 during movement into the work chamber 8. In contrast, in the embodiment shown in FIGS. 4 and 5 modified in this regard, the elastic intermediate region 6 of the pumping member 2 is made of material on the outer rigid ring or support member 7 on the edge side. Connected, for example by vulcanization, at this point, relative movement between the lower surface of the pumping member 2 on the side opposite to the working chamber 8 and the support member 7 is prevented or avoided. It has come to be.

  As can also be seen in FIG. 4, the maximum height h6 of the support member 7 is dimensioned larger than the thickness h1 of the elastic intermediate region 6, so that the support member 7 is elastic in the axial direction. The lower intermediate region 6 is reached below. The area reaching the lower side may be covered with an annular extension 11 provided in the pressure-feeding member 2 or the elastic intermediate area 6 and covered inside. As a result, the support of the elastic intermediate region 6 and the pumping member 2 is improved, and the positioning of the pumping member 2 inside the positive displacement pump 1 is improved as a whole.

  In the embodiment shown in FIGS. 4 and 5, there is a particularly suitable dimensional situation even in the edge region 5 where the pumping member 2 is fixed, clamped, tightened and / or possibly held in shape connection. Is set. The layer thickness h7 between the support member 7 and the protective layer 9 provided on the pumping member 2 can be dimensioned smaller than 0.5 times the maximum diameter D of the rigid drive member 3. The dimension can be set smaller than 0.15 times the thickness h1 of the elastic intermediate region 6. This can be achieved by supporting the pumping member 2 by the annular support member 7 in a relatively large area. The support member 7 extends from the outer sandwiching region 5 while being bent downward as viewed in a cross-sectional view, whereby the thickness of the pressure-feeding member 2 becomes an elastic intermediate region 6 toward the inner side. Increasing with the transition.

  The minimum layer thickness h7 between the support member 7 and the protective layer 9 or the diaphragm surface, that is, the surface of the pumping member 2, is 0.3 times the thickness h1 of the elastic intermediate region 6 in each form. May be set to a small size.

  Further different from the embodiment shown in FIGS. 1 to 3, in another embodiment shown in FIGS. 4 and 5, the connecting rod 4 that supports the drive member 3 is additionally provided with respect to the support member 7. As already mentioned, another support 10 on the inside for the pumping member 2 is provided. An elastic intermediate region 6 is placed on the support portion 10 at least during the maximum displacement of the pumping member 2 in the direction of the working chamber 8. This is illustrated in FIG. On the other hand, when the inner support portion 10 is lowered together with the driving member 3 in the reverse direction as shown in FIG. 4, the inner support portion 10 and the elastic intermediate region 6 are interposed. There is no contact, i.e. separation, over a large radial section.

  The amount of deformation of the elastic intermediate region 6 increases especially when displaced into the pumping chamber 8, and becomes maximum in the displaced state. Thus, as the load increases, the supportability of the inner support portion 10 increases. This becomes increasingly effective, whereby a corresponding material stress in the elastic intermediate region 6 can be avoided or at least prevented. Correspondingly, the life of the pressure feeding member 2 can be extended.

  In this embodiment, the other support portion 10 is larger than half of the sum of the diameter D extending in the radial direction of the drive member 3 and the inner diameter D6 of the outer support portion 7, but the inner diameter of the outer support portion 7 is larger. It has an outer diameter D5 that is smaller than D6. This provides a suitable ratio of supporting and holding the elastic pumping member 2 at different displacement positions, which can be seen in FIGS. 4 and 5.

  At least the surface or the lower surface of the pressure feeding member 2 opposite to the working chamber 8 may have a slip coating layer. This sliding coating layer reduces or minimizes sliding friction, in particular between the inner support 10 and the lower surface of the pumping member 2.

  The reciprocating positive displacement pump or diaphragm pump 1 has an elastic pressure feeding member 2 and an inner rigid driving member 3. The driving member 3 acts on the center of the elastic pressure-feeding member 2 and displaces the pressure-feeding member 2 up and down by the drive movement of the driving member 3. The pumping member 2 has an elastic intermediate region 6 and an edge-side clamping region 5, and the thickness h 1 of the elastic intermediate region 6 is between the driving member 3 and the edge-side support portion 7. The dimension is set to 0.3 times or more of the minimum free width a. This allows the diaphragm or pumping member 2 to receive a particularly thrust load when displaced, and thus have a long life.

1 Reciprocating positive displacement pump / diaphragm pump 2 Elastic pumping member 3 Drive member / hard member (steel member)
4 Connecting rod 5 Edge area of the pumping member (protrusion)
6 Elastic middle region 7 Outer support (housing side)
8 Working room 9 Protective layer 10 Supporting part (connecting rod side)
11 Annular extension a Free width h1 Thickness of pumping member h3 Layer thickness of elastic material h5 Axial length of steel member h6 Edge height of ring h7 Minimum layer thickness D Driving member / hard Diameter of member (steel member) Dk Diameter of concave area D3 Diameter of inner diaphragm D4 Diameter of pressed diaphragm D5 Outer diameter of support D6 Inner diameter of outer support α α Tangential angle

Claims (25)

An elastic pumping member (2), an inner rigid driving member (3) or a hard member acting at the center of the pumping member (2), and a radius with respect to the working portion of the driving member (3) In a reciprocating positive displacement pump comprising an elastic intermediate region (6) arranged on the outer side in the direction and an edge or outer clamping part (5) for an elastic pumping member (2),
An elastic intermediate region (6) between the outer or edge pinching part (5) and the inner hard member (3) is provided in the radial direction on the hard member (3) and the hard member (3). It has a thickness (h1) that is at least 0.3 times the smallest free width (a) between adjacent edges of the sandwiching and supporting members (7) facing each other. A reciprocating positive displacement pump.   The thickness of the elastic intermediate region (6) between the outer edge pinching part (5) and the inner hard member (3) is greater than 0.5 times the minimum free width (a) ( 2. The positive displacement pump according to claim 1, comprising h1).   3. Volumetric mold according to claim 1 or 2, wherein the inner rigid drive member (3) is connected in a material connection, for example by vulcanization, to the elastic intermediate region (6) or the pumping member (2). pump.   The axial length (h5) of the inner rigid drive member (3) coupled to the elastic part of the pumping member (2) is at least 0.7 times the minimum free width (a) The positive displacement pump according to any one of claims 1 to 3, which is dimensioned to a size.   The axial length (h5) of the inner rigid drive member (3) coupled to the elastic part (6) of the pumping member (2) has a minimum free width (a) of at least 1. The positive displacement pump according to any one of claims 1 to 4, which is dimensioned to be five times as large.   The positive displacement pump according to any one of claims 1 to 5, wherein a surface on the fluid side of the pressure feeding member (2) is formed in a concave shape.   The concave shape of the pumping member (2) has a concave ratio in which the ratio of the maximum depth (h4) to the diameter (Dk) of the entire concave area is at least 5/100 in a stress-free state. The positive displacement pump according to any one of claims 1 to 6.   The amount of displacement of the pumping member (2) from the stress-free state is at least 2/3 upwardly toward the work chamber (8), and a maximum of 1/3 downward from the work chamber (8). The positive displacement pump according to any one of claims 1 to 7, wherein:   The height (h5) coupled to the elastic part (6) of the rigid drive member (3) has at least 0.5 times the diameter of the rigid drive member (3), The positive displacement pump according to any one of claims 1 to 8.   The pumping member (2) has an additional protective layer (9), and the protective layer (9) is preferably formed thinner than the portion other than the protective layer of the pumping member (2), 10. A positive displacement pump according to any one of claims 1 to 9, which has a higher chemical resistance than an elastic material, for example made of polytetrafluoroethylene.   The elastomer layer thickness (h3) above the rigid drive member (3) up to the protective layer (9) or to the surface of the diaphragm or to the surface of the pumping member (2) is the rigidity of the rigid drive member (3). 11. A positive displacement pump according to any one of claims 1 to 10, which is dimensioned to be smaller than 0.15 times its maximum diameter.   The positive displacement pump according to any one of claims 1 to 11, wherein the pumping member (2) has a support portion or a support member (7) on the outer side of the edge side.   13. Volume according to any one of the preceding claims, wherein the outer support or support member (7) has an inner diameter (D3) that is smaller than the diameter (D4) that is loaded by the fluid pressure. Type pump.   The contour of the elastic intermediate region (6) rests on the outer support or support member (7) with a tangential angle (α) less than 50 ° in the state of bottom dead center, The positive displacement pump according to any one of claims 1 to 13.   The outer support (7) has, at least in a region directed towards the pumping member (2), a sliding covering layer for minimizing sliding friction, for example made of PTFE or molybdenum disulfide. Item 15. The positive displacement pump according to any one of Items 1 to 14.   The outer support (7) is made of a material with sliding friction minimized, for example by addition of PTFE or molybdenum disulfide, together with the material of the elastic intermediate layer or the material of the elastic pumping member (2). The positive displacement pump according to any one of claims 1 to 15, wherein the positive displacement pump is formed.   The positive displacement pump according to any one of claims 1 to 16, wherein the outer support (7) is made of a material having good thermal conductivity, for example, aluminum or an aluminum alloy.   18. Volume according to claim 1, wherein the material of the elastic intermediate layer or the material of the elastic pumping member (2) is a vulcanized elastomer or a thermoplastic elastomer, for example polyurethane. Type pump.   The support member (7) is formed as an outer rigid ring, and the elastic intermediate region (6) of the pumping member (2) is connected to the outer outer rigid ring, in particular in material connection. The positive displacement pump according to any one of claims 1 to 18, wherein the positive displacement pump is coupled by, for example, vulcanization.   20. The maximum height (h6) of the support member (7) is dimensioned larger than the thickness (h1) of the elastic intermediate region (6). Positive displacement pump.   The layer thickness (h7) between the support member (7) and the protective layer (9) is dimensioned less than 0.15 times the maximum diameter (D) of the rigid drive member (3). 21. A positive displacement pump according to any one of claims 1 to 20, which is dimensioned to be smaller than 0.15 times the thickness (h1) of the elastic intermediate region (6).   The minimum layer thickness (h7) between the support member (7) and the protective layer (9) or diaphragm surface is less than 0.3 times the thickness (h1) of the elastic intermediate region (6). The positive displacement pump according to any one of claims 1 to 21, which is dimensioned.   The connecting rod (4) is provided with another support (10) on the inside for the pumping member (2), on which the elastic intermediate region (6) is provided, 23. The positive displacement pump according to any one of claims 1 to 22, wherein the pump is mounted at least when the pumping member (2) is displaced in the direction toward the working chamber (8).   The other support (10) is larger than half of the sum of the diameter (D) of the drive member (3) and the inner diameter (D6) of the outer support (7), but the outer support (7) 24. The positive displacement pump according to any one of claims 1 to 23, having an outer diameter (D5) smaller than the inner diameter (D6).   25. At least the surface of the pumping member (2) opposite the working chamber (8) has a sliding coating layer for reducing or minimizing sliding friction. The positive displacement pump according to any one of the preceding claims.

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