JP3723668B2

JP3723668B2 - Internal gear pump

Info

Publication number: JP3723668B2
Application number: JP21921497A
Authority: JP
Inventors: 勝則石河; 春彦柴田
Original assignee: Toyooki Kogyo Co Ltd
Current assignee: Toyooki Kogyo Co Ltd
Priority date: 1997-07-29
Filing date: 1997-07-29
Publication date: 2005-12-07
Anticipated expiration: 2017-07-29
Also published as: JPH1144293A

Description

【０００１】
【発明の属する技術分野】
本発明は、内接歯車ポンプに関し、特に、自動車でのエンジン潤滑や、自動変速機等のためのポンプに用いて好適な内接歯車ポンプに関する。
【０００２】
【従来の技術】
このような内接歯車ポンプは、実開平３−３７２９３号公報に記載されており、このものの吐出が行われる部分近傍を別途示すと、図５のようになっている。すなわち、内歯歯車Ａと外歯歯車ＢはケースＣの一端面に開口した収容凹部Ｄに収容され、この収容凹部Ｄの開口を閉じる如く、この一端面に一端面を当接して設置する蓋部材Ｅを備えている。ケースＣの収容凹部Ｄ端壁とこれに対向する蓋部材Ｅの一端面部分には、吐出ポート凹部Ｆ、Ｇが形成され、これら吐出ポート凹部Ｆ、Ｇからは、収容凹部Ｄよりも径方向の外に延びた、吐出通路の一部を形成するための吐出通路用凹部Ｈ、Ｉがそれぞれ前記各一端面に開放して形成され、これらの吐出通路用凹部Ｈ、Ｉは、ケースＣへの蓋部材Ｅの当接設置により、収容凹部Ｄとともに閉じられるようになっている。
【０００３】
【発明が解決しようとする課題】
このものでは、吐出通路のための吐出通路用凹部Ｈ、Ｉが、各吐出ポート凹部Ｆ、Ｇから径方向の外側へ延びているため、この吐出通路用凹部Ｈ、Ｉの範囲内では、内歯歯車Ａの外周面が直接吐出通路用凹部Ｈ、Ｉに露呈する。このため吐出通路用凹部Ｈ、Ｉでの吐出流体が内歯歯車Ａの外周面に直接作用して内歯歯車Ａをその圧力で径方向へ押圧する。収容凹部Ｄの内径は内歯歯車Ａの外径より若干大きいのでこの押圧により内歯歯車Ａが若干移動し、吐出通路用凹部Ｈ、Ｉの箇所で内歯歯車Ａ外周と収容凹部内周Ｄ間の隙間が大きくなって、さらにまた、内歯歯車Ａ内部の歯先面のシール係合で吸入域と吐出域を分離している部分では、内歯歯車Ａの移動で歯先面の隙間が大きくなって、これら隙間を通る吐出域から吸入域への漏れが多くなり、容積効率が低下するとともに、前記押圧で内歯歯車Ａが収容凹部Ｄ内周面へ押しつけられる結果、トルク損失が増し、内接歯車ポンプの効率が低下する問題点がある。本発明は、このような問題点を解消しようとするものである。
【０００４】
【課題を解決するための手段】
このため、本発明では、内歯歯車の外周面を摺動自在に内周面で支持して内歯歯車とこれに噛み合う外歯歯車とを収容する収容凹部を一端面に開口形成したケースと、ケースの一端面に一端面を当接して収容凹部の開口を閉じるよう設置する蓋部材を備え、収容凹部の端壁と蓋部材の当接側端面の収容凹部端壁に対向する部分には、吐出域において吐出ポート凹部が形成され、ケースの一端面と蓋部材の当接側端面には、ケースへの蓋部材の当接設置により閉ざされて吐出通路の一部を形成する吐出通路用凹部が開放形成されている内接歯車ポンプにおいて、ケースと蓋部材の吐出通路用凹部がともに収容凹部よりも半径方向で外に形成され、吐出域と吐出通路を通じさせる連通手段が吐出ポート凹部と吐出通路用凹部を通じさせるトンネル状となる通孔であり、この通孔がケースと蓋部材の少なくとも一方に設けられるようにした。
【０００５】
なお、この場合、トンネル状となる通孔はケースと蓋部材の両方に設けても、どちらか一方にのみ（例えばケース）に設け、他方（例えば蓋部材）には通孔を設けないようにしてもよい。ケースと蓋部材の両方にこの通孔を設けたときには、吐出域からの吐出流体はそれぞれの吐出ポート凹部からこの通孔を経て吐出通路へ導かれるが、この通孔をどちらか一方にのみ（例えばケース）に設けたときには、吐出域からの吐出流体は、この通孔を設けた側の吐出ポート凹部から通孔を経て吐出通路に導かれ、他方（例えば蓋部材）の吐出ポート用凹部からは吐出通路へ導かれない。
【０００６】
そしてこのような構成によると、吐出通路用凹部は収容凹部よりも半径方向で外側にあって、吐出ポート凹部と吐出通路用凹部を通じさせるトンネル状となる通孔で吐出域からの吐出流体が吐出通路へ導かれるので、内歯歯車の外周面が吐出通路用凹部に露呈することはなく、吐出通路用凹部での吐出流体が、内歯歯車の外周面に直接押圧作用する事態を防止でき、吐出通路用凹部での吐出流体が内歯歯車の外周面に直接作用することにより内歯歯車が移動して漏れの増大やトルク損失の増大を招く事態を防止できる。
【０００７】
【実施例】
以下、自動車のエンジン潤滑用のポンプに適用した本発明の実施例を図面により説明する。１はケースで、内歯歯車２と、これに噛み合う外歯歯車３を収容した収容凹部４を、その一端面１Ａに開口して形成している。この収容凹部４の内周面は内歯歯車３の外周面を摺動自在に支持するようになっている。５は、その一端面５Ａを前記ケース１の一端面１Ａに当接して、収容凹部４の開口を閉じるように設置される蓋部材である。６は駆動軸で、前記外歯歯車３を回転駆動するよう、外歯歯車３に嵌合している。
【０００８】
収容凹部４の端壁４Ａには、吐出域に対応して吐出ポート凹部７と、吸入域に対応して吸入ポート凹部８が窪み形成されている。吸入ポート凹部８には、吸入通路用凹部９が収容凹部４の周壁を切り欠いて前記一端面１Ａに開放する態様で半径方向外側へ延びるよう連設されており、該凹部９は通孔１０を経て吸入開口１１に通じている。
【０００９】
１２は前記一端面１Ａに開放して収容凹部４の半径方向の外側に形成された吐出通路用凹部で、該凹部１２は通孔１３を経て吐出開口１４に通じている。そしてこの吐出通路用凹部１２と吐出ポート凹部７は、収容凹部４の周壁を切り欠くことのないトンネル状となった通孔１５によって通じている。そして、このように通孔１５により前記両凹部７、１２を通じるので、収容凹部４の端壁４Ａでは吐出ポート凹部７の外周側に内歯歯車２の周縁部分を覆う覆い部Ｘが形成される（図１参照）。１６はリリーフ弁設置筒部で、前記凹部１２の吐出流体が設定圧を越えて圧力上昇したとき、これを開口１７から逃がすリリーフ弁が収容されている。１８はこの開口１７と吸入通路用凹部９を通じる逃がし凹部である。
【００１０】
蓋部材５の前記一端面５Ａには、収容凹部４の端壁４Ａへの対向箇所に、前記吸入ポート凹部８に対応して吸入ポート凹部１９と、前記吐出ポート凹部７に対応して吐出ポート凹部２０が窪み形成され、さらに、吸入ポート凹部１９には、前記吸入通路用凹部１２に合致する吸入通路用凹部２１が一端面５Ａに開放して連設状に形成されるとともに、前記吐出通路用凹部１２に合致する吐出通路用凹部２２と、吸入通路用凹部２１に通じた前記逃がし凹部１８に合致する逃がし凹部２３が、一端面５Ａに開放してそれぞれ窪み形成されている。２４は吐出ポート凹部２０と吐出通路用凹部２２を通じさせる、一端面５Ａに開放しないトンネル状となった通孔である。このように通孔２４により両凹部２０、２２を通じさせるので、一端面５Ａでは吐出ポート凹部２０の外周に内歯歯車２の周縁部分を覆う覆い部Ｙが形成される（図１参照）。
【００１１】
そして、ケース１への蓋部材５の設置で吐出通路用凹部１２、２２は互いに合致して閉じ、これら凹部１２、２２と通孔１３により吐出開口１４へ通じた一連の吐出通路２５が形成され、吸入通路用凹部９、２１も互いに合致して閉じ、これら凹部９、２１と通孔１０により吸入開口１１へ通じた一連の吸入通路２６が形成され、また、逃がし凹部１８、２３も互いに合致して閉じ、前記開口１７からの逃がし流体を吸入通路２６へ合流させる一連の逃がし通路が形成される。
【００１２】
この実施例の作動を説明する。駆動軸６の回転で、両歯車２、３が回転されると、吸入通路２６からの流体を吸入し、これを吐出通路２５へ吐出するポンプ作動が行われ、このとき、吐出される流体は、各吐出ポート凹部７、２０から通孔１５、２４をそれぞれ通って吐出通路２５へと吐出される。内歯歯車２のこの吐出箇所近傍では、吐出通路用凹部１２、２２が収容凹部４とは半径方向の外方に隔てていて内歯歯車２の外周面が吐出通路用凹部１２、２２に露呈しない。このため内歯歯車２外周面に吐出流体が直接作用することはなく、吐出圧力が直接内歯歯車外周に作用して内歯歯車が径方向に押される事態が防止される。
【００１３】
そしてまた、収容凹部４の端壁４Ａでは吐出ポート凹部７の外周側に内歯歯車２の周縁部分を覆う覆い部Ｘが形成され、蓋部材５の一端面５Ａでは吐出ポート凹部２０の外周に内歯歯車２の周縁部分を覆う覆い部Ｙが形成されているので、これら覆い部により、吐出される流体が内歯歯車２の外周へ流入し該歯車２を径方向へ押圧する事態を抑えることができる。即ち、吐出箇所近傍で内歯歯車の周縁部分が吐出流体に直接露呈している場合と比較すると、覆い部Ｘ、Ｙと内歯歯車２の各端面との間の隙間が、吐出ポート凹部７、２０の吐出流体が内歯歯車２の外周へ流入する際に大きな絞り作用を及ぼし、この結果、吐出流体の内歯歯車２外周への流入を抑えて該歯車２が径方向へ押圧される事態を抑えることができるのである。
【００１４】
このように、本実施例では、吐出流体による内歯歯車２の径方向への押圧作用を抑えることができるので、内歯歯車２が吐出流体による押圧作用で径方向へ移動しその外周と収容凹部４の内周の隙間が吐出通路２５側で大きくなって、この大きくなった隙間を介し吐出流体の吸入側への漏れが多くなったり、また、前記内歯歯車２の移動で該歯車２内で吸入域と吐出域を分離する各歯車２、３の歯先でのシール隙間が大きくなってこの隙間を介する吐出流体の吸入側への漏れが多くなるといった事態の発生を抑えて容積効率の低下が防止できる。そしてまた、内歯歯車２の前記径方向への押圧作用が抑えられるため、内歯歯車２が径方向へ押圧される結果収容凹部４の内周へ強く接触してトルク損失が増すといった事態の発生も抑えることができ、効率の高いポンプが得られる。
【００１５】
なお、本実施例ではケース１と蓋部材５とに吐出ポート凹部７と吐出通路用凹部１２を通じる通孔１５と、吐出ポート凹部２０と吐出通路用凹部２２を通じる通孔２４をそれぞれ設けたが、通孔１５、２４のどちらか一方を省略しても良い。この場合通孔を省略した吐出ポート凹部（例えば通孔２４を省略したときには凹部２０）は吐出通路２５へ流体を吐出しないが、この吐出ポート凹部での吐出圧により、通孔を省略しない吐出ポート凹部での吐出圧による両歯車２、３への軸方向への押圧作用に抗して、両歯車２、３を軸方向へ押圧して、両歯車２、３への軸方向作用力を平衡化させるうえで役立つ。
【００１６】
そしてまた、図示した実施例は両歯車２、３の歯数差は１であるが、これを２以上として内歯歯車内での吸入域と吐出域の分離のために、吸入域から吐出域への移行部分に両歯車の歯先面が摺動係合する三日月形のシール片を設ける内接歯車ポンプとすることもできる。
【００１７】
【発明の効果】
このように本発明によると、内歯歯車の外周面が吐出通路用凹部に露呈することはなく、吐出通路用凹部での吐出流体が内歯歯車の外周面に直接作用することにより内歯歯車が押圧されて移動し漏れの増大やトルク損失の増大を招く事態を抑えて効率の高い内接歯車ポンプが得られる。
【図面の簡単な説明】
【図１】本発明の１実施例を示した、図２の線Ｂ−Ｂに沿った断面図。
【図２】図１の線Ａ−Ａに沿った断面図。
【図３】ケース１の右側面図。
【図４】蓋部材の左側面図。
【図５】従来例の要部を示す断面図。
【符号の説明】
１ケース
２内歯歯車
３外歯歯車
４収容凹部
５蓋部材
７、２０吐出ポート凹部
１２、２２吐出通路用凹部
１５、２４通孔
２５吐出通路[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an internal gear pump, and more particularly to an internal gear pump suitable for use in a pump for engine lubrication, automatic transmission, or the like in an automobile.
[0002]
[Prior art]
Such an internal gear pump is described in Japanese Utility Model Laid-Open No. 3-37293, and the vicinity of the portion where the discharge is performed is separately shown in FIG. That is, the internal gear A and the external gear B are accommodated in an accommodation recess D opened at one end surface of the case C, and the lid is installed with the one end surface in contact with the one end surface so as to close the opening of the accommodation recess D. A member E is provided. Discharge port recesses F and G are formed on the end wall of the housing recess D of the case C and the one end surface portion of the lid member E opposite to the end wall, and the discharge port recesses F and G have a radial direction from the housing recess D. The discharge passage recesses H and I for forming a part of the discharge passage are formed open to the respective one end surfaces, and these discharge passage recesses H and I are connected to the case C. The cover member E is closed and installed together with the housing recess D.
[0003]
[Problems to be solved by the invention]
In this case, since the discharge passage recesses H and I for the discharge passage extend radially outward from the discharge port recesses F and G, within the range of the discharge passage recesses H and I, The outer peripheral surface of the toothed gear A is directly exposed to the discharge passage recesses H and I. For this reason, the discharge fluid in the discharge passage recesses H and I directly acts on the outer peripheral surface of the internal gear A to press the internal gear A in the radial direction with the pressure. Since the inner diameter of the housing recess D is slightly larger than the outer diameter of the internal gear A, the internal gear A slightly moves by this pressing, and the outer periphery of the internal gear A and the inner periphery D of the housing recess at the discharge passage recesses H and I. In the portion where the suction region and the discharge region are separated by the seal engagement of the tooth tip surface inside the internal gear A, the clearance of the tooth tip surface is moved by the movement of the internal gear A. As a result, the leakage from the discharge area passing through these gaps to the suction area increases, the volumetric efficiency decreases, and the internal gear A is pressed against the inner peripheral surface of the housing recess D by the pressing, resulting in torque loss. This increases the efficiency of the internal gear pump. The present invention is intended to solve such problems.
[0004]
[Means for Solving the Problems]
For this reason, in the present invention, a case in which an outer peripheral surface of the internal gear is slidably supported by the inner peripheral surface and an accommodation recess for accommodating the internal gear and the external gear meshing with the internal gear is formed in one end surface. A lid member that is disposed so as to abut one end surface of the case to close the opening of the housing recess, and the end wall of the housing recess and the portion facing the housing recess end wall of the abutting side end surface of the lid member A discharge port recess is formed in the discharge area, and the discharge passage is closed at the one end surface of the case and the contact-side end surface of the cover member by forming the cover member in contact with the case to form a part of the discharge passage. In the internal gear pump in which the recesses are formed open, the discharge passage recesses of the case and the lid member are both formed radially outward from the housing recesses, and the communication means for passing the discharge area and the discharge passages is the discharge port recess. Tunnel through discharge channel recess A through hole which becomes, the through hole is to be provided on at least one of the case and the lid member.
[0005]
In this case, even though the tunnel-shaped through hole is provided in both the case and the lid member, it is provided only in one (for example, the case) and the other (for example, the lid member) is not provided with a through hole. May be. When this through hole is provided in both the case and the lid member, the discharge fluid from the discharge area is guided to the discharge passage from each discharge port recess through this through hole. For example, when provided in the case), the discharge fluid from the discharge region is guided to the discharge passage through the through hole recess on the side where the through hole is provided, and from the discharge port recess on the other side (for example, the lid member). Is not led to the discharge passage.
[0006]
According to such a configuration, the discharge passage recess is radially outward from the receiving recess, and the discharge fluid is discharged from the discharge region through a tunnel-shaped through hole that passes through the discharge port recess and the discharge passage recess. Since it is guided to the passage, the outer peripheral surface of the internal gear is not exposed to the discharge passage concave portion, and the discharge fluid in the discharge passage concave portion can be prevented from directly acting on the outer peripheral surface of the internal gear, It is possible to prevent a situation where the discharge fluid in the recess for the discharge passage directly acts on the outer peripheral surface of the internal gear and the internal gear moves to cause an increase in leakage and torque loss.
[0007]
【Example】
Embodiments of the present invention applied to an automobile engine lubrication pump will be described below with reference to the drawings. Reference numeral 1 denotes a case, which has an accommodation recess 4 that accommodates an internal gear 2 and an external gear 3 that meshes with the internal gear 2 and that is open to one end face 1A. The inner peripheral surface of the housing recess 4 slidably supports the outer peripheral surface of the internal gear 3. Reference numeral 5 denotes a lid member that is installed so that its one end face 5 </ b> A is in contact with one end face 1 </ b> A of the case 1 and the opening of the housing recess 4 is closed. Reference numeral 6 denotes a drive shaft which is fitted to the external gear 3 so as to rotationally drive the external gear 3.
[0008]
A discharge port recess 7 corresponding to the discharge area and a suction port recess 8 corresponding to the suction area are formed in the end wall 4 </ b> A of the housing recess 4. The suction port recess 8 is connected to the suction passage recess 9 so as to extend radially outward in a manner that the peripheral wall of the housing recess 4 is cut out and opened to the one end surface 1A. To the suction opening 11.
[0009]
Reference numeral 12 denotes a discharge passage recess which is open to the one end surface 1A and is formed on the outer side in the radial direction of the housing recess 4. The recess 12 communicates with the discharge opening 14 through a through hole 13. The discharge passage recess 12 and the discharge port recess 7 communicate with each other through a tunnel-like through hole 15 that does not cut out the peripheral wall of the housing recess 4. Since the recesses 7 and 12 are passed through the through hole 15 in this way, a cover X that covers the peripheral portion of the internal gear 2 is formed on the outer peripheral side of the discharge port recess 7 on the end wall 4A of the receiving recess 4. (See FIG. 1). Reference numeral 16 denotes a relief valve installation cylinder portion that houses a relief valve that allows the fluid discharged from the recess 12 to escape from the opening 17 when the pressure rises beyond a set pressure. Reference numeral 18 denotes an escape recess through the opening 17 and the suction passage recess 9.
[0010]
On the one end surface 5A of the lid member 5, the suction port concave portion 19 corresponding to the suction port concave portion 8 and the discharge port corresponding to the discharge port concave portion 7 are provided at positions opposite to the end wall 4A of the housing concave portion 4. A recess 20 is formed in the recess, and a suction passage recess 21 that matches the suction passage recess 12 is formed in the suction port recess 19 so as to be continuous with the one end surface 5A. A discharge passage recess 22 that matches the recess 12 for the discharge and an escape recess 23 that matches the escape recess 18 that communicates with the recess 21 for the suction passage are formed on the one end surface 5A so as to be recessed. Reference numeral 24 denotes a through-hole formed in a tunnel shape that does not open to the one end surface 5 </ b> A and is made to pass through the discharge port recess 20 and the discharge passage recess 22. Thus, since both the recessed parts 20 and 22 are let through by the through-hole 24, the cover part Y which covers the peripheral part of the internal gear 2 is formed in the outer periphery of the discharge port recessed part 20 in 5 A of one end surfaces (refer FIG. 1).
[0011]
Then, when the lid member 5 is installed in the case 1, the discharge passage recesses 12, 22 are closed in conformity with each other, and a series of discharge passages 25 communicating with the discharge opening 14 are formed by the recesses 12, 22 and the through holes 13. The suction passage recesses 9 and 21 are also closed in conformity with each other to form a series of suction passages 26 that lead to the suction opening 11 by the recesses 9 and 21 and the through holes 10, and the escape recesses 18 and 23 are also aligned with each other. A series of relief passages are formed that close and close together to allow the escape fluid from the opening 17 to join the suction passage 26.
[0012]
The operation of this embodiment will be described. When both the gears 2 and 3 are rotated by the rotation of the drive shaft 6, a pump operation is performed to suck fluid from the suction passage 26 and discharge it to the discharge passage 25. At this time, the discharged fluid is The discharge port recesses 7 and 20 are discharged into the discharge passage 25 through the through holes 15 and 24, respectively. In the vicinity of the discharge location of the internal gear 2, the discharge passage recesses 12, 22 are spaced radially outward from the housing recess 4, and the outer peripheral surface of the internal gear 2 is exposed to the discharge passage recesses 12, 22. do not do. For this reason, the discharge fluid does not act directly on the outer peripheral surface of the internal gear 2, and the situation where the discharge pressure acts directly on the outer periphery of the internal gear and the internal gear is pushed in the radial direction is prevented.
[0013]
In addition, a cover portion X that covers the peripheral portion of the internal gear 2 is formed on the outer peripheral side of the discharge port recess 7 on the end wall 4A of the housing recess 4, and on the outer periphery of the discharge port recess 20 on the one end surface 5A of the lid member 5. Since the cover part Y which covers the peripheral part of the internal gear 2 is formed, the situation in which the fluid discharged flows into the outer periphery of the internal gear 2 and presses the gear 2 in the radial direction is suppressed by these cover parts. be able to. That is, compared with the case where the peripheral portion of the internal gear is directly exposed to the discharge fluid in the vicinity of the discharge location, the gap between the cover portions X and Y and each end surface of the internal gear 2 is the discharge port recess 7. , 20 exerts a large squeezing action when flowing into the outer periphery of the internal gear 2, and as a result, the gear 2 is pressed in the radial direction while suppressing the discharge fluid from flowing into the outer periphery of the internal gear 2. The situation can be suppressed.
[0014]
As described above, in this embodiment, the pressing action in the radial direction of the internal gear 2 by the discharged fluid can be suppressed, so that the internal gear 2 moves in the radial direction by the pressing action by the discharged fluid and the outer periphery and the housing are accommodated. The gap on the inner periphery of the recess 4 becomes larger on the discharge passage 25 side, and the leakage of discharged fluid to the suction side increases through the enlarged gap, and the gear 2 is moved by the movement of the internal gear 2. The volume efficiency is reduced by suppressing the occurrence of a situation in which the seal gap at the tooth tips of the gears 2 and 3 separating the suction area and the discharge area in the inside increases and leakage of the discharged fluid to the suction side through the gap increases. Can be prevented. In addition, since the pressing action of the internal gear 2 in the radial direction is suppressed, the internal gear 2 is pressed in the radial direction, resulting in a strong contact with the inner periphery of the housing recess 4 and an increase in torque loss. Occurrence can also be suppressed, and a highly efficient pump can be obtained.
[0015]
In this embodiment, the case 1 and the lid member 5 are provided with a through hole 15 through the discharge port recess 7 and the discharge passage recess 12 and a through hole 24 through the discharge port recess 20 and the discharge passage recess 22, respectively. However, one of the through holes 15 and 24 may be omitted. In this case, the discharge port recess in which the through hole is omitted (for example, the recess 20 when the through hole 24 is omitted) does not discharge fluid to the discharge passage 25, but the discharge port does not omit the through hole due to the discharge pressure in the discharge port recess. The axial action force on both gears 2 and 3 is balanced by pressing both gears 2 and 3 in the axial direction against the pressing action in the axial direction on both gears 2 and 3 due to the discharge pressure in the recess. It helps to make it.
[0016]
In the illustrated embodiment, the difference in the number of teeth between the gears 2 and 3 is 1, but this is set to 2 or more to separate the suction area and the discharge area in the internal gear from the suction area to the discharge area. An internal gear pump may be provided in which a crescent-shaped seal piece in which the tooth tip surfaces of both gears are slidably engaged with each other at the transition portion is provided.
[0017]
【The invention's effect】
As described above, according to the present invention, the outer peripheral surface of the internal gear is not exposed to the discharge passage recess, and the discharge gear in the discharge passage recess directly acts on the outer peripheral surface of the internal gear. The internal gear pump with high efficiency can be obtained while suppressing the situation where the pressure is pushed and moved, leading to an increase in leakage and an increase in torque loss.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view taken along line BB in FIG. 2, showing one embodiment of the present invention.
FIG. 2 is a cross-sectional view taken along line AA in FIG.
3 is a right side view of case 1. FIG.
FIG. 4 is a left side view of a lid member.
FIG. 5 is a cross-sectional view showing a main part of a conventional example.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Case 2 Internal gear 3 External gear 4 Accommodating recessed part 5 Cover member 7, 20 Discharge port recessed part 12, 22 Discharge path recessed part 15, 24 Through hole 25 Discharge path

Claims

内歯歯車の外周面を摺動自在に内周面で支持して内歯歯車とこれに噛み合う外歯歯車とを収容する収容凹部を一端面に開口形成したケースと、ケースの一端面に一端面を当接して収容凹部の開口を閉じるよう設置する蓋部材を備え、収容凹部の端壁と蓋部材の一端面の収容凹部端壁に対向する部分には、吐出域において吐出ポート凹部が形成され、ケースの一端面と蓋部材の一端面には、ケースへの蓋部材の当接設置により閉ざされて吐出通路の一部を形成する吐出通路用凹部が開放形成されている内接歯車ポンプにおいて、ケースと蓋部材の吐出通路用凹部がともに収容凹部よりも半径方向で外に形成され、吐出域と吐出通路を通じさせる連通手段が吐出ポート凹部と吐出通路用凹部を通じさせるトンネル状となる通孔であり、この通孔がケースと蓋部材の少なくとも一方に設けられた内接歯車ポンプ。A case in which an outer peripheral surface of the internal gear is slidably supported by the inner peripheral surface and an accommodation recess for accommodating the internal gear and the external gear meshing with the opening is formed in one end surface, and one end surface of the case is A lid member is provided so as to close the opening of the receiving recess by contacting the end face, and a discharge port recess is formed in the discharge area in the portion facing the receiving recess end wall of the end wall of the receiving recess and one end surface of the lid member. An internal gear pump in which a discharge passage recess is formed on one end surface of the case and one end surface of the lid member so as to be closed by contact and installation of the lid member to the case to form a part of the discharge passage. In this case, the discharge passage recesses of the case and the lid member are both formed radially outward from the receiving recesses, and the communication means for passing the discharge area and the discharge passage is a tunnel-like passage through the discharge port recess and the discharge passage recess. Is a hole, and this through hole Over scan and internal gear pump provided on at least one of the lid member.