JP4823029B2 - Screw type pump device - Google Patents

Description

  The present invention relates to a screw-type pump device, and more particularly to a screw-type pump device suitable for supplying lubricating oil to a required lubrication part such as a transmission gear and a synchromesh mechanism of a manual transmission for an automobile.

  As a screw type pump device for supplying a liquid, for example, there is one disclosed in FIG. 6 of Japanese Patent Laid-Open No. 2003-65275 (Patent Document 1). This is because the liquid refrigerant is sent from the low pressure side (suction side) to the high pressure side (discharge side) by the fluid frictional force between the threaded portion (screw groove) provided on the outer periphery of the rotor and the liquid refrigerant (liquid). To do. In this pump device, a rotor member having a pressure feeding member (rotor) and a shaft is rotatably supported by a bearing member in a substantially cylindrical housing, and is rotated by a motor through the shaft. Yes. A male screw is machined on the outer periphery of the pressure feeding member so as to send the liquid refrigerant from the suction port side at one end in the axial direction to the discharge port side at the other end. An annular member having a smooth inner peripheral surface is disposed on the inner periphery of the housing so as to surround the outer peripheral surface of the pressure feeding member.

In the screw-type liquid refrigerant pump having the above-described configuration, when the motor is driven, the rotor member rotates in the same direction, and the liquid refrigerant flowing in from the suction side is a gap between the pressure-feeding member whose outer periphery is machined with the annular member. The fluid friction force is generated in the gap portion by the rotational movement of the pressure feeding member, and the liquid refrigerant is pulled by the outer peripheral surface of the pressure feeding member to move to the discharge side and discharged to the outside of the pump.
Japanese Patent Laying-Open No. 2003-65275 (paragraphs [0004] to [0007], FIG. 6).

  1 and 4 show an example in which the above-described screw-type pump device of Patent Document 1 is applied to lubrication of a transmission gear and a synchromesh mechanism of an automobile manual transmission. That is, a housing 10 having a cylindrical inner peripheral surface 10a is integrally formed on one side of a transmission case (not shown) of a manual transmission for an automobile, and a transmission gear and a synchromesh mechanism ( An output shaft 11 provided with a not-shown) is rotatably supported so as to be coaxial with the inner peripheral surface 10 a of the housing 10. The inner surface of the rotor 1 is fitted to the outer peripheral surface of the intermediate portion of the output shaft 11 over its entire length, and the key 15 is engaged with each of the key grooves 15a and 2 formed in the output shaft 11 and the rotor 1 to thereby output the output shaft. 11, the inner end concave step portion 1 c is brought into contact with the step portion 11 b of the output shaft 11, and is spline-engaged with the protruding shaft portion 11 c that protrudes coaxially from the front end surface 11 a of the output shaft 11. The front end surface of the flange joint 14 abuts on the outer end of the rotor 1 and is fixed to the output shaft 11 by tightening with a nut 14a.

  The rotor 1 has a cylindrical portion 1a whose outer peripheral surface is slidably fitted to the inner peripheral surface 10a of the housing 10, and a cylindrical protrusion whose outer diameter is smaller than the cylindrical portion 1a and protrudes from one end thereof toward the flange joint 14 side. A threaded portion 21 is formed on the outer peripheral surface of the cylindrical portion 1a. A suction chamber R1 and a discharge chamber R2 are formed between the housing 10 and the shaft 11 on both ends in the axial direction of the cylindrical portion 1a, and the cylindrical protrusion 1b protrudes into the discharge chamber R2. The output shaft 11 is coaxially formed with a transmission gear and a synchromesh mechanism from a position slightly ahead of the front end surface 11a to the vicinity of the position where the transmission gear 13 and the synchromesh mechanism are provided. Is formed in a radial communication path 12 that communicates with the distal end of the delivery path 13 and has the other end opened on the outer peripheral surface of the output shaft 11. The cylindrical projection 1b is formed with a window hole 22 that always communicates the radial communication path 12 with the discharge chamber R2. Although this technique is known as such, there is no literature describing such a structure.

  In the above-described prior art, lubricating oil splashing in the transmission case is always introduced into the suction chamber R1, and the output shaft 11 and the rotor 1 rotate forward as indicated by the arrow A in FIG. The lubricating oil in the suction chamber R1 is fed into the discharge chamber R2 by the threaded portion 21 on the outer periphery of the cylindrical portion 1a. The lubricating oil is fed into the window hole 22, the radial communication passage 12 and the delivery passage as shown by an arrow f in FIG. 13 is supplied to a lubricating portion such as a transmission gear and a synchromesh mechanism of the transmission to lubricate them. However, in a state in which the transmission is switched to reverse, the output shaft 11 and the rotor 1 rotate in the direction opposite to the arrow A in FIG. 4 and the lubricating oil in the discharge chamber R2 is fed back into the suction chamber R1 by the screw portion 21. Since the lubricating oil in the lubrication required parts such as the transmission gear of the transmission and the synchromesh mechanism is sucked out in the direction opposite to the arrow f in FIG. 1, the lubrication of these parts is insufficient. If the transmission is switched from this state to forward, the lubricating oil in the suction chamber R1 passes through the discharge chamber R2 and is sent into the lubrication required portion from the window hole 22, the radial communication passage 12 and the delivery passage 13. Since it takes some time to return the sucked lubricating oil into the lubrication part, there may be a problem due to insufficient lubrication in the meantime. Such a problem due to insufficient supply of fluid is not limited to the case of a manual transmission for an automobile, but always occurs in a device that temporarily reverses during operation.

  An object of the present invention is to solve such a problem in a screw type pump device by preventing fluid such as lubricating oil from being sucked out from a supply destination during reverse rotation.

  To this end, a screw type pump device according to the present invention includes a housing having a cylindrical inner peripheral surface, a shaft rotatably supported coaxially with the inner peripheral surface, and an inner portion of the housing provided on the shaft. A rotor having a cylindrical portion with a threaded portion formed on an outer peripheral surface that is rotatably fitted to the peripheral surface, and a suction chamber and a discharge chamber are respectively provided between a housing and a shaft that are positioned on both ends in the axial direction of the cylindrical portion. In the formed screw-type pump device, the rotor is composed of a cylindrical portion and a cylindrical protrusion that is coaxially formed integrally therewith and protrudes into the discharge chamber, and the inner peripheral surface is rotatably fitted to the outer peripheral surface of the shaft. A delivery passage formed so as to be relatively rotatable between a first angular position with respect to the shaft and a second angular position separated from the first angular position, and further extending in the axial direction in the shaft; A radial communication path formed at a position overlapping with the cylindrical protrusion, one end communicating with the delivery path and the other end opened on the outer peripheral surface of the shaft, and formed on the cylindrical protrusion of the rotor. A window that opens the radial communication path and communicates the discharge chamber with the delivery passage in the state of the first angular position, and closes the discharge chamber from the delivery passage by closing the radial communication path in the state of the second angular position. It is characterized by having a hole.

  In the screw-type pump device described in the preceding paragraph, a key groove is formed on one of the outer peripheral surface of the shaft and the inner peripheral surface of the rotor, and a half of the key is embedded, and the key remains on the other It is preferable that the rotor is relatively rotatable between the first angular position and the second angular position with respect to the shaft by forming an engagement groove having a fan-shaped cross section with which the half is engaged.

  3. The screw type pump device according to the preceding item 2, wherein the shaft is a part of an output shaft of an automobile transmission provided with lubrication parts such as a transmission gear and a synchromesh mechanism, and a housing is a transmission case of the automobile transmission. In the state where the lubricating oil scattered in the transmission case is guided to the suction chamber and the radial communication passage is opened by the window hole, the lubricating oil in the discharge chamber passes through the delivery passage and requires lubrication. A screw type pump device characterized by being guided to a part.

  According to the first aspect of the present invention, the rotor includes a cylindrical portion and a cylindrical protrusion that is coaxially formed integrally therewith and protrudes into the discharge chamber, and an inner peripheral surface is rotatably fitted to the outer peripheral surface of the shaft. A delivery passage formed so as to be relatively rotatable between a first angular position with respect to the shaft and a second angular position separated from the first angular position, and further extending in the axial direction in the shaft; A radial communication path formed at a position overlapping with the cylindrical projection of the rotor and having one end communicating with the delivery path and the other end opened to the outer peripheral surface of the shaft, and the cylindrical projection of the rotor. On the other hand, in the state at the first angular position, the radial communication path is opened to connect the discharge chamber to the delivery path, and in the second angle position, the radial communication path is closed to shut off the discharge chamber from the delivery path. Since it has a window hole, the rotor When the shaft rotates in one direction, the first angular position with respect to the shaft rotates due to the frictional resistance with the inner peripheral surface of the housing, and the shaft rotates with the shaft, and the discharge chamber communicates with the delivery passage. The fluid sent from the suction chamber to the discharge chamber by the section is supplied from the delivery passage to the supply destination. On the other hand, when the shaft rotates in the reverse direction, the friction with the inner peripheral surface of the housing causes The angular position of 2 is rotated together with the shaft, and the discharge chamber is blocked from the delivery passage, so that no fluid is sucked out from the supply destination. That is, even if the shaft is reversed, the already supplied fluid is not sucked out from the supply destination. Therefore, as long as the reverse rotation is temporary, there is no problem due to insufficient supply of fluid.

  A fan-shaped cross-sectional shape in which a key groove is formed on one of the outer peripheral surface of the shaft and the inner peripheral surface of the rotor, and the half of the key is embedded, and the remaining half of the key is engaged with the other According to the invention of claim 2, the rotor can be relatively rotated between the first angular position and the second angular position with respect to the shaft by forming the engagement groove. The engagement groove that engages with the remaining half of the key that transmits rotation has a fan-shaped cross section. When the shaft rotates in one direction, fluid is automatically supplied to the supply destination. When rotating in the reverse direction, it is possible to automatically prevent the fluid from being sucked out from the supply destination.

  The shaft is a part of the output shaft of the transmission for automobiles provided with lubrication required parts such as the transmission gear and the synchromesh mechanism, the housing is formed integrally with the transmission case of the transmission for automobiles, 4. The invention according to claim 3, wherein the lubricating oil scattered in the machine case is guided and the lubricating oil in the discharge chamber is guided to the lubricating portion through the delivery passage when the radial communication passage is opened by the window hole. According to the present invention, a part of an output shaft of an automobile transmission is used as a shaft, a rotor is attached to the shaft, and a housing is integrally provided in a transmission case of the automobile transmission. A screw-type pump device is obtained in which the lubricating oil supplied to the lubrication required part of the automobile transmission during forward travel is sucked out during backward travel and does not cause a problem due to insufficient lubrication. Door can be.

  The best mode for carrying out the screw type pump device according to the present invention will be described below with reference to FIGS. As in the prior art described in FIGS. 1 and 4, this embodiment is applied to supply lubricating oil to lubrication required parts such as a transmission gear and a synchromesh mechanism of a manual transmission for an automobile. 11 is the same as the above-described prior art except for the structure for attaching the rotor 20 to the motor 11.

  As shown mainly in FIG. 1, a housing 10 in which a cylindrical inner peripheral surface 10a is formed is integrally formed on one side of a transmission case (not shown) of a manual transmission for an automobile, and a transmission gear and a synchromesh. The distal end portion of the output shaft of a manual transmission provided with a mechanism (not shown) is rotatably supported by the transmission case so as to be coaxial with the inner peripheral surface 10a, and the distal end portion of the output shaft is this embodiment. It becomes the shaft 11 of this. The inner surface of the rotor 20 is rotatably fitted to the outer peripheral surface of the intermediate portion of the shaft 11 over its entire length, and the half of the key 15 is embedded in the key groove 15a formed on the outer peripheral surface of the shaft 11. By engaging the remaining half part with an engagement groove 23 having a fan-shaped cross section formed on the inner peripheral surface of the rotor 20 so as to be movable in the circumferential direction, the key 15 comes into contact with one end in the circumferential direction of the engagement groove 23. The first angular position to be stopped (see the key 15 indicated by the solid line in FIG. 3) and the second angular position to be stopped by contacting the other end of the engagement groove 23 with a predetermined angle α away from it (see FIG. 3). Relative to the shaft 11 between the two-dot chain line 15A).

  The rotor 20 has a recessed step portion 20c formed on the inner peripheral surface side of the inner end on the transmission case side, abutting against the step portion 11b of the shaft 11, and a protruding shaft that protrudes coaxially from the distal end surface 11a of the shaft 11. The flange joint 14 that is spline-engaged with the portion 11c has its distal end abutted against the distal end surface 11a of the shaft 11 to prevent the rotor 20 from coming off freely, and is tightened by a nut 14a screwed into the distal end side of the projecting shaft portion 11c. By this, it is fixed to the output shaft 11. The rotor 20 includes a cylindrical portion 20a whose outer peripheral surface is slidably fitted to the inner peripheral surface 10a of the housing 10, and a cylindrical protrusion that has an outer diameter smaller than the cylindrical portion 20a and protrudes from one end thereof toward the flange joint 14 side. It is an integral body composed of the portion 20b. A suction chamber R1 and a discharge chamber R2 are formed between the housing 10 and the shaft 11 on both ends in the axial direction of the cylindrical portion 20a. Lubricating oil scattered in the transmission case is introduced into the suction chamber R1, and The cylindrical protrusion 20b protrudes into the discharge chamber R2. Lubricating oil in the suction chamber R1 is applied to the outer peripheral surface of the cylindrical portion 20a during the forward rotation of the output shaft 11 (when the automobile is moving forward), in the discharge chamber R2 due to fluid friction with the inner peripheral surface 10a of the housing 10. A screw portion 21 having a trapezoidal cross section is formed. The number of threads 21 may be singular or plural.

  A delivery passage 13 is formed coaxially from the vicinity of the front end surface 11a of the output shaft 11 toward a portion inside the transmission case where the transmission gear and the synchromesh mechanism are provided, and in the vicinity of the front end surface 11a of the output shaft 11, A pair of radial communication passages 12 having one end communicating with the delivery passage 13 and the other end opened on the outer peripheral surface of the output shaft 11 are formed at positions overlapping the cylindrical protrusion 20b in the axial direction. When the rotor 20 is in the first angular position with respect to the shaft 11, the radial communication passage 12 is opened at the cylindrical projection 20 b of the rotor 20 to open the discharge chamber R 2 to the delivery passage 13 as shown by the solid line in FIG. In the state of being in the second angular position, a window hole 22 that closes the radial communication path 12 and blocks the discharge chamber R2 from the delivery path 13 is formed as shown by a two-dot chain line 12A in FIG. .

  The output shaft 11 is connected through a flange joint 14 to a propeller shaft (not shown) that drives the drive wheels. Further, the gap between the output shaft 11 and the rotor 20 and between the flange joint 14 and the output shaft 11 are sealed by an O-ring 24 and an O-ring 14b, and the gap between the boss portion of the flange joint 14 and the housing 10 is a wall portion of the discharge chamber R2. Sealed by a part of the oil seal 16.

In the above-described embodiment, when the automobile moves forward, the output shaft 11 and the rotor 20 rotate normally as indicated by the arrow A in FIG. 3, and the rotor 20 contacts the shaft 11 due to frictional resistance with the inner peripheral surface 10 a of the housing 10. 2 and 3, the first angular position indicated by the solid line in FIG. 2 and FIG. 3 is automatically set, and the radial communicating path 12 is opened by the window hole 22 and rotates together with the shaft 11. Therefore, the threaded portion 21 on the outer periphery of the cylindrical portion 20a. The lubricating oil fed from the suction chamber R1 into the discharge chamber R2 through the window hole 22, the radial communication path 12, and the delivery path 13 as shown by the arrow f in FIG. 1 and the transmission gear and synchromesh mechanism of the transmission Lubricate the lubrication part. When the transmission is switched to reverse, the output shaft 11 and the rotor 20 rotate in the direction opposite to the arrow A in FIG. 3, and the screw portion 21 on the outer periphery of the cylindrical portion 20a removes the lubricating oil from the discharge chamber R2 into the suction chamber R1. Try to suck in. However, in this case as well, the rotor 20 is delayed with respect to the shaft 11 due to the frictional resistance with the inner peripheral surface 10a of the housing 10, and the second angular position indicated by two-dot chain lines 12A and 15A in FIGS. Since the radial communication path 12 is closed by the window hole 22, the lubricating oil in the lubrication required parts such as the transmission gear of the transmission and the synchromesh mechanism passes through the radial communication path 12 and the window hole 22 from the delivery path 13. It is not sucked out in the direction opposite to the arrow f in FIG. Since the backward movement in the automobile is temporary and can be switched to the forward movement in a short time, the lubrication oil remaining in the lubrication required part is sufficient for the lubrication during the backward movement, and there is no problem due to the lack of lubricating oil. When the transmission is switched to forward, the rotor 20 is in the first angular position with respect to the output shaft 11, and the lubricating oil in the discharge chamber R2 is supplied to the lubrication required portion. By engaging the remaining half of the key 15 with the half embedded in the key groove 15 a formed in the shaft 11 in the sector-shaped engagement groove 23 formed in the rotor 20, the rotor 20 can be moved in the circumferential direction. The relative rotation with respect to the shaft 11 is possible between the first angular position and the second angular position, and the engagement groove 23 formed in the rotor 20 has a very simple structure in which the cross-sectional shape is a fan shape. If this happens, the lubricating oil is automatically supplied to the required lubrication parts such as the transmission gears and the synchromesh mechanism in the transmission. You can prevent the problem. The same effect can be obtained by forming a key groove on the rotor 20 and an engagement groove having a fan-shaped cross section on the shaft 11.

  Further, in the above-described embodiment, the case where the present invention is applied to supply of lubricating oil in an automobile manual transmission has been described. However, the present invention is not limited to this, and a device that temporarily reverses during operation. The present invention can be widely applied when supplying a necessary working fluid.

It is a longitudinal section explaining the whole structure of one embodiment of the screw type pump device by the present invention. It is 2-2 sectional drawing of FIG. FIG. 3 is a 3-3 cross-sectional view of FIG. 1. It is sectional drawing equivalent to FIG. 3 of this kind of screw type pump apparatus by a prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Housing, 10a ... Inner peripheral surface, 11 ... Shaft (output shaft), 12 ... Radial direction communication path, 13 ... Delivery path, 15 ... Key, 15a ... Key groove 1, 20 ... Rotor, 20a ... Cylindrical part, 20b ... Cylindrical protrusion, 21 ... Threaded part, 22 ... Window hole, 23 ... Engagement groove, R1 ... Suction chamber, R2 ... Discharge chamber.

Claims (3)

A housing formed with a cylindrical inner peripheral surface, a shaft rotatably supported coaxially with the inner peripheral surface, and an outer periphery provided on the shaft and rotatably fitted with the inner peripheral surface of the housing In a screw type pump device comprising a rotor having a cylindrical portion with a thread portion formed on the surface, and a suction chamber and a discharge chamber formed between the housing and the shaft located on both ends in the axial direction of the cylindrical portion,
The rotor is composed of the cylindrical portion and a cylindrical protrusion that is coaxially formed integrally therewith and protrudes into the discharge chamber, and an inner peripheral surface is rotatably fitted to an outer peripheral surface of the shaft, The first angular position and a second angular position that is a predetermined angle away from the first angular position are provided to be relatively rotatable,
A delivery passage formed in the shaft so as to extend in an axial direction;
A radial communication path formed at a position overlapping the cylindrical protrusion of the shaft, one end communicating with the delivery path and the other end opened to the outer peripheral surface of the shaft;
When the rotor is in the first angular position with respect to the shaft, the radial communication passage is opened to communicate the discharge chamber with the delivery passage. A screw-type pump device comprising: a window hole that closes the radial communication path and blocks the discharge chamber from the delivery path in a state of being at an angular position of 2.   2. The screw type pump device according to claim 1, wherein a key groove is formed on one of an outer peripheral surface of the shaft and an inner peripheral surface of the rotor that are fitted to each other, and a half of the key is embedded in the other. Forming an engagement groove having a fan-shaped cross-sectional shape with which the remaining half of the key is engaged, thereby rotating the rotor relative to the shaft between the first angular position and the second angular position. A screw type pump device characterized by being movable.   3. The screw-type pump device according to claim 1 or 2, wherein the shaft is a part of an output shaft of an automobile transmission provided with lubrication parts such as a transmission gear and a synchromesh mechanism, and the housing is for an automobile. It is formed integrally with a transmission case of the transmission, and the lubricating oil scattered in the transmission case is guided to the suction chamber, and the discharge chamber is opened in the state where the radial communication path is opened by the window hole. The screw-type pump device is characterized in that the lubricating oil is guided to the lubrication required portion through the delivery passage.

Images