JP6271166B2 - Inscribed gear pump - Google Patents

Description

  The present invention relates to an internal gear pump having the features of the premise of claim 1.

  Inscribed gear pumps are known. The internal gear pump has a ring gear, that is, a gear having internal teeth, and a gear having external teeth arranged eccentrically in the ring gear, and this gear is hereinafter referred to as a pinion. A ring gear and a pinion, also called a gear of an internal gear pump, mesh with each other in the circumferential section. In another circumferential section where the two gears of the inscribed gear pump do not mesh with each other, the ring gear and the pinion define a sickle-shaped pump space between them, which is a push-away space, free Also called space or intermediate space. A separating member is arranged in the pump space, and this separating member is also referred to as a sickle or sickle member based on a normal shape that matches the shape of the pump space. Another term for the separating member is a filling member. The separation member separates the suction area from the discharge area of the pump space of the internal gear pump, the suction area communicates with the pump inlet, and the discharge area communicates with the pump outlet. May be understood as the inlet or outlet of an inscribed gear pump.

  The tooth tips of the ring gear and pinion teeth are in contact with the separating member on the outside or inside, and slide along the separating member on the outside and inside when the inscribed gear pump is driven, that is, in the pinion and ring gear that is driven to rotate. To do. The separating member confines the fluid volume in the space between the ring gear and the pinion teeth, so that the gears can draw fluids in the pumping space of the inscribed gear pump when driving in rotation, i.e. driving the inscribed gear pump. To the discharge area.

  An axial disk is known in order to seal the pump space in the axial direction on the end face side of the ring gear and pinion. This axial disk is usually a plate-like member, and this plate-like member is pressure-loaded on the outer side opposite to the ring gear and pinion, so that the inner side facing the ring gear and pinion is inward. That is, it is pressed against the end face side of the ring gear and pinion. Such an axial disk is also called a pressure plate. The pressure load on the outside is usually performed in a position-limited region, that is, a so-called pressure region. This pressure region communicates with the discharge region of the pump space or the pump outlet. This means that the same pressure is formed in the pressure region as in the discharge region and in the pump outlet. The seal on the end face side of the ring gear and the pinion need not be hermetically sealed, and leakage may occur. On the one hand, an optimization between good lubrication and low friction of the ring gear and pinion inside the axial disk, on the other hand, a slight leakage loss should be achieved. The height of the pressing force of the axial disc against the ring gear and pinion end faces is determined by the size of the pressure region. The shape and arrangement of the pressure zones associated with the pump space and the separating member are also important for the seal. The pressure zone is formed outside the axial disk and / or inside the end wall of the pump housing facing the axial disk.

  When the gear is driven to rotate, the inter-tooth space of the gear moves along the outer side and the inner side of the separating member, and opens toward the discharge region of the pump space of the inscribed gear pump at the end of the separating member. A pilot control notch is known to avoid a sudden pressure rise when the interdental space opens towards the discharge area. The pilot control notch is a notch, a groove, etc. that extends from the discharge area to the suction area slightly longer from the tooth root circle to the tooth tip circle inside the axial disk. . The pilot control notch is open inside the axial disk, that is, toward the gear. In a typical manner, the cross section of the pilot control notch is reduced from the discharge area to the suction area, and the cross section of the pilot control notch is small enough to act as a restriction, so The pressure gradually decreases in the direction away from the discharge area. By this pilot control notch, the pressure in the interdental space in the separation member region rises to the pressure in the discharge region in an ideal manner up to the end on the discharge region side when the gear of the inscribed gear pump is driven to rotate. Therefore, no pressure jump occurs when the interdental space opens toward the discharge region at the end of the separating member during the rotation of the gear.

  The object of the present invention is to improve an internal gear pump of the type mentioned at the beginning.

  An inscribed gear pump according to the invention having the features of claim 1 has at least one pilot control passage that is pressure-loaded, the pilot control passage being in the region of the separating member. The ring gear and / or pinion has an opening between the root circle and the tip circle.

  The pilot control passage may be configured, for example, as a drill or punch. Because the pilot control passage increases the pressure in the interdental space of the gear of the inscribed gear pump, the pressure jump is at least reduced when the interdental space at the end of the separating member opens toward the discharge region, Preferably, the pressure in the interdental space in the region of the separating member is adapted to the pressure in the discharge region of the inscribed gear pump, so that when the interdental space opens towards the discharge region, the pressure jump is Does not occur. It works to prevent pressure pulsation and noise formation. An additional advantage of the present invention is in the pilot control notch where the cross section and thus the action of the pilot control passage is flattened by the wear of the axial disk, i.e. the cross section is reduced by the wear of the axial disk. As described above, there is no change due to wear. Another advantage of the present invention is that the crimping force of the separating member at the tooth tip of the gear is reduced. This is because the hydraulic pressure in the interdental space that pushes the separating member away from the tooth tip increases. This reduces friction and wear and increases the efficiency of the inscribed gear pump. The present invention further provides that the temperature or viscosity dependence of the pressure regulation by the pilot control passage is generally slightly longer than the longer pilot control notch as compared to the cross section, particularly when the pilot control passage is configured to be short. It has the advantage of being.

  The dependent claims contain preferred embodiments and variants of the invention described in claim 1.

  In the region of the separating member, a plurality of openings that are shifted in the circumferential direction, that is, at different positions in the longitudinal direction of the separating member, between the ring gear and / or the pinion tooth circle and the tooth tip circle of the pinion gear pump. By means of the pilot control passage, as described in claim 2, the pressure in the interdental space is increased stepwise to the pressure in the discharge area during the rotation of the gear, and large pressure jumps are avoided.

  The present invention does not necessarily assume the presence of the axial disk, and the pilot control passage is provided between the ring gear and / or the pinion root circle and the tip circle of the inward gear pump housing. You may open through an end wall or a side wall. Of course, it is preferable to provide an axial disk which is pressure-loaded outside the gear and the separating member and is penetrated by the pilot control passage. It is sufficient for the axial disk to have a pilot control passage on the end face side of the gear and the separating member.

  The inscribed gear pump according to the invention is provided in particular as a hydraulic pump for hydraulic skid control and / or powered vehicle brake devices, this inscribed gear pump being used for skid control. Also called a return pump.

It is a side view of the internal gear pump by this invention. It is a top view of the axial disk of the internal gear pump of FIG. 1 by this invention.

  The present invention will be described in detail below with reference to embodiments shown in the drawings.

  The internal gear pump 1 according to the present invention shown in FIG. 1 has two gears 2 and 3, that is, a ring gear 2 having an internal tooth row, and an external tooth row called a pinion 3 in the illustrated embodiment. And a gear. The pinion 3 is arranged eccentrically in the ring gear 2, and the two gears 2 and 3 have axes parallel to each other and mesh with each other. The ring gear 2 is rotatably slidably supported in the bearing ring 4, and the pinion 3 is disposed on the pump shaft 5 so as not to rotate relative to the pump shaft 5. In order to drive the internal gear pump 1, the pump shaft 5 is rotationally driven, and the pinion 3 coupled to the pump shaft 5 so as not to rotate relative to the pump shaft 5 rotates and meshes with the pinion 3. The ring gear 2 is driven to rotate. The direction of rotation is indicated by arrow P.

  The gears 2 and 3 define a sickle-shaped pump space 6 between the gears 2 and 3 in a circumferential section that is not meshed with each other. Within the pump space 6, a sickle-like separating member 7 consisting of a plurality of parts is arranged, and this separating member 7 may be interpreted as partly sickle-like or semi-sickle-like, and based on its shape, It is also called a sickle member. The separating member 7 separates the suction area 8 from the discharge area 9 of the pump space 6. An inlet hole 10 is opened in the suction region 8, and an outlet hole 13 extends from the discharge region 9 through a slit 11 of an axial disk 12 described later. The tooth tips of the gears 2 and 3 of the internal gear pump 1 are in contact with the outer side or the inner side of the separating member 7 and slide along the outer side or the inner side of the separating member 7 when the gears 2 and 3 are rotationally driven. The separating member 7 has the same width as the gears 2 and 3, and the two gears 2 and 3 have the same width. Since the separation member 7 confines the fluid volume in the interdental space of the gears 2 and 3, the fluid is pumped from the suction region 8 to the discharge region 9 by the rotational drive of the gears 2 and 3. At the end on the suction region side, the separation member 7 is supported by a support portion 14, and the support portion 14 is formed by a pin that penetrates the pump space 6 in the lateral direction.

The separating member 7 has an arched outer leg 15 and an similarly arched inner leg 16, and these legs 15, 16 extend from the support 14 toward the discharge region 9. doing. The outer side of the outer leg 15 is curved in an arc shape with the same radius of curvature as the tooth tip circle d _k of the ring gear 2, and the tooth tip of the ring gear 2 is tightly connected to the outer side of the outer leg 15. And slides along the outer side of the outer leg 15 during rotational driving. The inside of the inner leg 16 is curved in an arc shape with the same radius of curvature as the tip circle dk of the pinion 3, and the tooth tip of the pinion 3 is closely packed inside the inner leg 16. It abuts and slides along the inner side of the inner leg 16 during rotational driving. The tooth tips of the gears 2 and 3 do not need to be in airtight contact with the legs 15 and 16 of the separating member 7, and leakage flow is allowed. At the end portions on the support member side and the suction region side, the legs 15 and 16 are hinged to each other so as to be pivotable. The torsion spring 17 disposed between the legs 15 and 16 presses the legs 15 and 16 away from each other, thereby pressing the outer leg 15 toward the tooth tip of the ring gear 2 and the inner leg 16 to the pinion. Press toward 3 tooth tips. The seal member 18 disposed between the two legs 15 and 16 at the end on the support side and the suction area side seals between the two legs 15 and 16 and the axial disk 12. An intermediate space between the two legs 15, 16 communicates with the outlet hole 13 through the slit 11 in the axial disk 12, and this intermediate space between the two legs 15, 16 is used when the internal gear pump 1 is driven. Pressure is applied. A pin 19 penetrating the inner leg 16 in the lateral direction holds the separating member 7 in the support portion 14. Since the separation member 7 is open at the end on the discharge area side, the intermediate space between the two legs 15 and 16 is also in communication with the discharge area 9.

  The inscribed gear pump 1 has one axial disk 12 on each end face side of the gears 2 and 3, and FIG. 2 shows a view of the axial disk 12 from the inside facing the gears 2 and 3. It is shown. The axial disk 12 is pierced by the pump shaft 5 and a pin that forms the support portion 14, and is thereby held so as not to be relatively rotatable. The axial disk 12 includes a plurality of holes for allowing the pump shaft 5, the support portion 14, and the pin 19 to pass therethrough. The axial disk 12 extends in the circumferential direction over 180 ° or more from the suction area 8 partially covered by the axial disk 12, beyond the separation member 7 and the discharge area 9. The axial disk 12 has the slit 11 for the pump outlet, and the slit 11 extends in an arch shape between the tooth tips of the gears 2 and 3 and crosses the outlet hole 13. The inlet hole 10 opens into the suction area 8 of the pump space 6 in front of the axial disk 12 when viewed in the rotational direction P of the gears 2 and 3.

  On the outer side opposite to the gears 2 and 3, the axial disk 12 has a pressure region 20, which extends in the circumferential direction from the vicinity of the support portion 14 to the discharge region 9, and in the radial direction. The gears 2 and 3 extend substantially to the root circle df. Each axial disk 12 has one pressure region 20. The pressure region 20 is a flat recess provided outside the axial disk 12, and this recess communicates with the discharge region 9 and the outlet hole 13, whereby the outside of the axial disk 12 is pressure-loaded, The inside is pressed against the end faces of the gears 2 and 3 and the end face of the separating member 7 for sealing. The pressure region 20 is sealed with a seal, and this seal is disposed along the circumferential surface of the pressure region in the circumferential direction. This seal is not shown in the drawing.

  The axial disk 12 has a plurality of pilot control passages 21, and these pilot control passages 21 penetrate from the outside to the inside. The pilot control passage 21 is configured as a cylindrical hole in the illustrated embodiment, but, of course, the present invention is not forced to this. Since the pilot control passage 21 is arranged with a circumferential interval between the tooth tip circle dk and the tooth root circle df of the ring gear 2 and the pinion 3, the space between the teeth is rotated when the gears 2 and 3 are rotated. When matched with 21, the interdental space of the gears 2 and 3 communicates with the pressure region 20, and further communicates with the outlet hole 13 through the pressure region 20. The interdental space is pressure-loaded by the pilot control passage 21. Since the pilot control passage 21 has a small diameter, the pilot control passage 21 acts as a throttle for reducing the pressure from the outside to the inside of the axial disk 12. As a result, the pressure in the interdental space of the gears 2 and 3 rises stepwise from the pilot control passage 21 to the pilot control passage 21 to the pressure in the discharge region 9 when the gear rotates. Since the pilot control passage 21 in the vicinity of the suction region 8 has a smaller diameter and cross section than the pilot control valve 21 in the vicinity of the discharge region 9, the pilot control passage 21 in the vicinity of the suction region 8 The pressure is lowered more strongly than the pilot control passage 21 in the vicinity of 9. The pilot control passage 21 acts to adjust the pressure from the suction area 8 toward the discharge area 9 within the interdental space of the gears 2 and 3, so that the interdental space is separated from the separating member 7 when the gears 2 and 3 are rotated. The pressure in the interdental space does not increase rapidly to the pressure in the discharge region 9 when the end of the discharge region is reached and opened toward the discharge region 9.

  In the region where the teeth of the gears 2, 3 of the internal gear pump 1 mesh with each other again at the end of the discharge region 9, the axial disk 12 has a flat recess as a pressure-bonding oil groove 22 on the inner side facing the gears 2, 3. have. The interdental space of the gears 2 and 3 of the inscribed gear pump 1 communicates with the discharge region 9 through the crimping oil groove 22. When the gears 2 and 3 are engaged again, it is avoided that the pumped fluid is confined in the interdental space into which the teeth of the different gears 3 and 2 enter. Such fluid confinement results in a significant increase in pressure based on excessive bearing load.

  This inscribed gear pump 1 is provided as a hydraulic pump of a hydraulic vehicle brake device (not shown). In this vehicle brake device, the inscribed gear pump 1 is, for example, an anti-lock brake as a so-called return pump. It is used to perform skid control such as control, traction slip control and / or beagle dynamic control and / or for creating brake pressure in a hydraulic powered vehicle brake system. Abbreviations ABS, ASR, FDR and ESP are commonly used for the skid control, and beagle dynamic control is also slang termed as overspeed prevention control.

1 Inscribed gear pump 2 Ring gear (gear)
3 Pinion (gear)
4 Bearing ring 5 Pump shaft 6 Pump space 7 Separating member 8 Suction area 9 Discharge area 10 Inlet hole 11 Slit 12 Axial disk 13 Outlet hole 14 Supporting part 15 Outer leg 16 Inner leg 17 Torsion spring 18 Seal member 19 Pin 20 Pressure Area 21 Pilot control path 22 Crimp oil groove dk Tooth tip circle df Tooth root circle

Claims (3)

An inscribed gear pump having a ring gear (2) and a pinion (3). The ring gear (2) and the pinion (3) mesh with each other in a circumferential section, and in another circumferential section. The ring gear (2) and the pinion (3) define a pump space (6) between them, and a separating member (7) is disposed in the pump space (6). The member (7) is of a type separating the suction area (8) of the pump space (6) from the discharge area (9) of the pump space (6),
In the circumferential section in which the separating member (7) is arranged, at least one pressure-loaded pilot control passage (21) is connected to the root circle (df) of the ring gear (2) and / or the pinion (3). ) And the tip circle (dk)
Within the circumferential section in which the separating member (7) is arranged, a plurality of the pressure-controlled pilot control passages (21) are displaced in the circumferential direction so that the ring gear (2) and / or the pinion (3) An opening between the root circle (df) and the tip circle (dk),
The pilot control passage (21) forms a throttle that reduces the pressure when flowing through, and the pilot control passage (21) that opens in the vicinity of the discharge region (9) has the suction region (8). characterized that you have a cross section larger than the pilot control passage that opens in the vicinity of (21), the internal gear pump. The inscribed gear pump (1) has an axial disk (12) that is movable in the axial direction and cannot be relatively rotated, and the axial disk (12) serves as a side seal as the ring gear (2) and The pinion (3) and the separation member (7) are arranged on the end face side, and are pressure-loaded on the outer side opposite to the ring gear (2), the pinion (3) and the separation member (7). One or a plurality of pilot control passages (21) of the axial disk (12) facing the ring gear (2), the pinion (3) and the separating member (7) from the pressure-loaded outside The inscribed gear pump according to claim 1, which communicates with the inside.   The inscribed gear pump according to claim 1, wherein the one or more pilot control passages (21) communicate with the pump outlet (13) of the inscribed gear pump (1).

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