Internal gear pump and internal gear motor

Abstract

Provided are an internal gear pump and an internal gear motor. The internal gear pump includes an internal gear rotatably fitted in a main body, an external gear internally engaged with the internal gear and meshed, a filler dividing a liquid delivery space formed between the internal gear and the external gear into a high-pressure region and a low-pressure region, and a sealing member covering both end surfaces of the two gears in a rotational axis direction, sealing the liquid delivery space, and having a communication groove formed to communicate a surrounding space surrounded by the filler and a tooth slot of the at least one gear with the high-pressure region, the communication groove being formed to continuously increase a sectional area communicating with the surrounding space as a rotation phase of the two gears advances, and an increase rate thereof rising in an accelerated manner.

Description

Technical Field

[0001] This invention relates to an internal gear pump and an internal gear motor. Background Technology

[0002] As a hydraulic power source for industrial vehicles, construction machinery, agricultural machinery, etc., an internal gear pump is used, comprising: a set of internal and external gears meshing with each other within a housing, and a crescent-shaped lock (also called a filler) dividing the fluid delivery space formed between these two gears into a high-pressure region and a low-pressure region. In Patent Document 1, a pressure inlet groove is provided on the cover of a sealing member that connects to the sides of the two gears, allowing the surrounding space between the crescent-shaped lock and the gear teeth to communicate with the high-pressure region. In this type of internal gear pump, oil is introduced from the high-pressure region to the gear teeth through the pressure inlet groove, thereby gradually increasing the pressure of the oil accumulated in the gear teeth as the gears rotate. This reduces vibration of the side plates or pump noise caused by the rapid increase in pressure of the oil accumulated in the gear teeth during rotation.

[0003] [Existing technical documents] [Patent Literature] Patent Document 1: Japanese Patent Application Publication No. 4-203373 Summary of the Invention [The problem the invention aims to solve] However, in internal gear pumps, for example, which include a pressure inlet channel with a monotonous shape such as a straight line, the pressure balance in the delivery space may sometimes break down when the pump speed is changed from low to high, and the pump's performance and durability may be reduced.

[0004] This problem has been diligently studied, and the inventors have discovered that in existing internal gear pumps that include a single pressure inlet groove with a monotonous shape, the timing of the pressure rise within the rotating gear groove is delayed when the gear is rotating at high speed compared to when it is rotating at low speed. Furthermore, the inventors have repeatedly studied this issue and found that in existing internal gear pumps, due to the large discrepancy in the timing of the pressure rise within the gear groove during high and low speeds, the proportion (area) of the high-pressure region in the delivery space differs significantly between high and low speeds. Therefore, when the pump speed is changed, for example, from low to high speed, there is a concern that the pressure balance may collapse due to the drastic change in the proportion of the high-pressure region in the delivery space, leading to a decrease in pump performance and durability. This phenomenon can also be described as occurring in internal gear motors with a structure similar to this.

[0005] Therefore, the main objective of this invention is to reduce the timing deviation of pressure changes in the gear grooves during low and high rotation in internal gear pumps and internal gear motors.

[0006] [Technical means to solve the problem] The first aspect of the present invention relates to an internal gear pump, comprising: an internal gear rotatably fitted into a body; an external gear internally meshing and engaging with the internal gear; a filler that divides a liquid delivery space formed between the internal gear and the external gear into a high-pressure region and a low-pressure region; and a sealing member that covers both end faces of the two gears in the direction of their rotational axes to seal the liquid delivery space, and having a connecting groove for communicating a surrounding space surrounded by the filler and the tooth grooves of at least one gear with the high-pressure region, the connecting groove being formed such that the cross-sectional area communicating with the surrounding space continuously increases as the rotational phase of the two gears advances, and the rate of increase increases in an accelerating manner.

[0007] Furthermore, a second aspect of the present invention relates to an internal gear motor, comprising: an internal gear rotatably fitted into a main body; an external gear internally meshing and engaging with the internal gear; a filler that divides a fluid delivery space formed between the internal gear and the external gear into a high-pressure region and a low-pressure region; and a sealing member that covers both end faces of the two gears in the direction of their rotational axes to seal the fluid delivery space, and having a connecting groove for communicating a surrounding space surrounded by the filler and the tooth grooves of at least one gear with the low-pressure region, wherein the connecting groove is formed such that the cross-sectional area communicating with the surrounding space continuously increases as the rotational phase of the two gears advances, and the rate of increase increases in an accelerating manner.

[0008] [The effects of the invention] According to the configuration of the present invention, the connecting groove is formed such that its cross-sectional area continuously increases with the advancement of the rotational phase of the two gears, and the rate of increase increases at an accelerating rate. Therefore, the amount of working fluid (oil, etc.) introduced from the connecting groove into the gear tooth grooves can be increased more rapidly with rotation. Thus, compared to conventional designs that only form a single, monotonous connecting groove, the timing of pressure changes within the tooth grooves during low rotation is not significantly advanced, but the timing of pressure changes within the tooth grooves during high rotation is significantly advanced only. Consequently, in internal gear pumps and internal gear motors, the deviation in the timing of pressure changes within the tooth grooves during low and high rotation can be reduced, improving pump performance and durability. Attached Figure Description

[0009] Figure 1 This is a longitudinal sectional view showing the structure of an internal gear pump according to a first embodiment of the present invention.

[0010] Figure 2 This is a cross-sectional view showing the structure of the internal gear pump of the described embodiment.

[0011] Figure 3 It is an enlarged representation Figure 2 The diagram in section A.

[0012] Figure 4 It is an enlarged representation Figure 2 The diagram in section B.

[0013] Figure 5 This is a diagram showing the relationship between the rotational phase of the internal gear pump in the described embodiment and the total cross-sectional area of ​​the connecting groove.

[0014] Figure 6 This is a graph showing the relationship between the rotational phase of the internal gear pump in the described embodiment and the pressure in the gear teeth.

[0015] Figure 7 It is a magnified diagram showing the structure around the connecting channels when there are multiple connecting channels and the timing of the connection between the channels is consistent.

[0016] Figure 8 This is a graph showing the relationship between the rotational phase of an internal gear pump and the total cross-sectional area of ​​the connecting channels when there are multiple connecting channels and the timing of their connection is consistent.

[0017] Figure 9 This is a graph showing the relationship between the rotational phase of an internal gear pump and the pressure within the gear slots when there are multiple connecting slots and the timing of the connection between the slots is consistent.

[0018] Figure 10 This is a cross-sectional view showing the structure of an internal gear pump according to a second embodiment of the present invention.

[0019] Figure 11 It is an enlarged representation Figure 10 The diagram in section C.

[0020] Figure 12 It is an enlarged representation Figure 10 The diagram of part D.

[0021] Figure 13 This is a diagram showing in detail the structure of the inner and outer connecting grooves of the embodiment described.

[0022] Figure 14 This is a diagram showing the relationship between the rotational phase of the internal gear pump in the described embodiment and the total cross-sectional area of ​​the connecting groove.

[0023] Figure 15 This is a graph showing the relationship between the rotational phase of the internal gear pump in the described embodiment and the pressure in the gear teeth.

[0024] Figure 16 This is a diagram showing the structure of the connecting groove of an internal gear pump in another embodiment.

[0025] [Explanation of Symbols] 100: Internal gear pump, internal gear motor 1: Main body 11: Sidewall 2: Internal gear 21: Alveolar teeth 3: External gear 31: Alveolar teeth 4: Filler 41: Outer circumference 42: Inner circumferential surface 5: Sealing components (side plates) 51: Connecting port 6: Connecting slot 61: Side 6 o : Outer connecting groove 6 i Inner connecting groove 7: Front Cover 8: Rear Cover 9: Drive shaft P i : Suction port P o Spray outlet R H High-voltage area R L Low-pressure area T o : Surrounding space T i Inner surrounding space Detailed Implementation [1] First implementation form The internal gear pump 100 of the first embodiment of the present invention will be described below with reference to the accompanying drawings.

[0026] (1) Overall structure The internal gear pump 100 of this embodiment is used as a hydraulic source for applications such as industrial vehicles, construction machinery, and agricultural machinery. It is configured to draw in fluid (such as mineral oil; also called working fluid) and eject it by rotating a set of internal gears 2 and external gears 3 housed within the main body 1. Specifically, as... Figure 1 and Figure 2 As shown, the internal gear pump 100 includes a main body 1, an internal gear 2, an external gear 3, a filler 4, and a sealing member 5.

[0027] Main body 1 is a hollow, roughly cylindrical body. For example... Figure 1 As shown, the opening at one axial end of the main body 1 is blocked by the front cover 7, and the opening at the other end is blocked by the rear cover 8. Figure 2 As shown, suction ports P for drawing in oil are formed on the side wall 11 of the main body 1. i and the nozzle P used for injecting oil o A through hole that connects to the surrounding structure.

[0028] The internal gear 2 is a ring-shaped gear comprising a plurality of radially inward teeth 22, and is so-called an internal gear. The internal gear 2 is rotatably fitted and housed within the body 1 with its axis of rotation parallel to the axial direction of the body 1.

[0029] The external gear 3 is an external gear comprising a plurality of radially outward teeth 32, and is a so-called pinion. The reference circle diameter of the external gear 3 is smaller than that of the internal gear 2, and its number of teeth is less than that of the internal gear 2. Furthermore, the external gear 3 is configured to mesh with the internal gear 2 in a manner where its axis of rotation is parallel to the axis of rotation of the internal gear 2. Figure 2 As shown, a fluid delivery space is formed between the external gear 3 and the internal gear 2. A drive shaft 9 for rotating the external gear 3 is connected to the rotating shaft of the external gear 3.

[0030] The filler 4 is positioned between the internal gear 2 and the external gear 3 within the main body 1, dividing the liquid delivery space into a high-pressure zone R. H With low-pressure area R L Specifically, the filler 4 is a crescent shape integrally protruding from the front cover 7, including an outer peripheral surface 41 that contacts the tooth tips of the internal gear 2, and an inner peripheral surface 42 that contacts the tooth tips of the external gear 3. The outer peripheral surface 41 has the same circular diameter as the tooth tip diameter of the internal gear 2, and simultaneously contacts multiple tooth tips of the internal gear 2, sealing the oil accumulated in its tooth groove 21. The inner peripheral surface 42 has the same circular diameter as the tooth tip diameter of the external gear 3, and simultaneously contacts multiple tooth tips of the external gear 3, sealing the oil accumulated in its tooth groove 31. Figure 2 As shown, a plurality of surrounding spaces T (also called outer surrounding spaces T) are formed between the filler 4 and the internal gear 2, which are surrounded by the outer peripheral surface 41 of the filler 4 and the tooth groove 21 of the internal gear 2. o Furthermore, a plurality of surrounding spaces T (also called inner surrounding spaces T) are formed between the filler 4 and the external gear 3, surrounded by the inner peripheral surface 42 of the filler 4 and the tooth groove 31 of the external gear 3. i In addition, the high-pressure region R H and low-pressure area R L Connect to the suction port P via ports not shown. i and spray outlet P o Connected.

[0031] In this embodiment, the sealing member 5 is inserted between the main body 1 and the two gears 2 and 3 in a manner that covers both end faces of the internal gear 2 and the external gear 3, thereby sealing the liquid delivery space. Specifically, the sealing member 5 (also called a side plate) is a plate-shaped member with a certain thickness that can slide axially into the inner circumference of the main body 1.

[0032] The sealing member 5 is provided with a communication port 51, which allows the high-pressure area R to communicate with the high-pressure area R. H The space between the sealing member 5 and the front cover 7 (or rear cover 8) is connected. The connection port 51 is formed by a through hole penetrating the sealing member 5 along the thickness direction, and opens on both sides of the sealing member 5. Multiple (specifically two) connection ports 51 are provided on the sealing member 5, and each connection port 51 is located in the high-pressure area R when viewed from the rotation axis direction. H The position where the teeth 22 of the rotating internal gear 2 and the teeth 32 of the external gear 3 pass over it.

[0033] Furthermore, the sealing member 5 is formed with a feature for connecting the high-pressure area R. H A connecting channel 6 surrounds the space T. The connecting channel 6 is used to transfer oil from the high-pressure region R. H It is introduced into the relatively low-pressure surrounding space T, causing the pressure within the surrounding space T to gradually increase.

[0034] In this internal gear pump 100, the external gear 3 and internal gear 2 are rotated by the drive shaft 9, allowing the pump to flow from the suction port P. i The oil drawn in is from the nozzle P o It is ejected. Specifically, when the external gear 3 rotates with the internal gear 2 that meshes with it, it is ejected from the intake port P. i Towards low-pressure region R L The oil, used as the working fluid, is introduced and enclosed within the surrounding space T and transported to the high-pressure area R. H From the nozzle P o It sprays out.

[0035] Furthermore, in the internal gear pump 100 of this embodiment, the connecting groove 6 is formed such that, as the rotational phase of the two gears 2 and 3 advances, the cross-sectional area communicating with the space T continuously increases, and the rate of increase increases in an accelerating manner. Specifically, in the internal gear pump 100 of this embodiment, a plurality of grooves are formed that connect the space T with the high-pressure region R. H The interconnected connecting slots 6 are configured to, with each connecting slot 6, cause the high-pressure region R to rotate with the rotation of the internal gear 2 and the external gear 3. H The timing of connection with space T is different from that of connection.

[0036] More specifically, such as Figure 3 and Figure 4 As shown, a high-pressure region R is formed on the sealing member 5 as a connecting groove 6. H With the inner surrounding space T i Multiple interconnected inner grooves 6 i and to make the high-voltage region R H Surrounding space T o Multiple interconnected outer connecting slots 6 o Furthermore, each inner connecting groove 6 i The high-pressure region R is affected by the rotation of gears 2 and 3. H With the inner surrounding space T i The timing of the connection is different for each of the six outer connecting slots. o The high-pressure region R is affected by the rotation of gears 2 and 3. H Surrounding space T o The timing of their connection differs.

[0037] The sealing member 5 has multiple inner connecting grooves 6, each having the same number (three in this case). i 6 external connecting slots o Moreover, these connecting slots 6 i 6 o Formed such that, with the rotation of the two gears 2 and 3, the inner side surrounds the space T i Reaching each inner connecting groove 6 i The timing and the outer surrounding space T o Reaching each outer connecting slot 6 o The timing was consistent.

[0038] Specifically, each connecting groove 6 is needle-shaped, formed along the side of the sealing member 5. More specifically, each connecting groove 6 is formed such that its base end is connected to the high-pressure region R. H The connecting port 51 is connected, and its front end faces straight toward the space T. Here, each connecting slot 6 has a shape that tapers at the front end as it faces the front end.

[0039] The connecting slots 6, which are connected to the common space T, are arranged at approximately equal intervals away from the central axis of the main body 1. Furthermore, they are formed to be approximately parallel to each other from the connecting port 51 toward the space T. The depth, width, and length of these connecting slots 6 may differ or be the same. Here, the further away from the central axis of the main body 1, the shorter the length of each connecting slot 6.

[0040] In addition, these multiple connecting channels 6 span the high-voltage region R H Formed in a manner that separates the space T with teeth 22 and teeth 32, the high-pressure region R is created. H It is connected to the surrounding space T adjacent to it. Specifically, each inner connecting slot 6 iTo cross the high-pressure area R H With the inner surrounding space T i The external gear 3 is formed with teeth 32. Each outer connecting groove 6 o To cross the high-pressure area R H Surrounding space T o The teeth 22 of the separated internal gear 2 are formed in a manner.

[0041] Furthermore, the positions of the front ends of each of these connecting slots 6 are set such that, with the rotation of gears 2 and 3, the timing of tooth grooves 21 and 31 reaching the front ends of each connecting slot 6 is different. Specifically, the multiple connecting slots 6 that are connected in a common manner around the space T are formed such that the rotational phases of the tooth surfaces 2b and 3b on the front side of the rotational direction of tooth grooves 21 and 31 constituting gears 2 and 3 are different from each other when they reach the front ends of each connecting slot 6. For example, as Figure 3 As shown, multiple inner connecting slots 6 i The tooth surface 3b on the front side of the tooth groove 31 in the rotational direction (i.e., the tooth surface on the rear side in the rotational direction included by the tooth 32) of the external gear 3 reaches each inner connecting groove 6. i The rotation phases of their front ends are different. Additionally, as... Figure 4 As shown, multiple outer connecting slots 6 o The tooth surface 2b on the front side of the tooth groove 21 in the rotational direction (i.e., the tooth surface on the rear side in the rotational direction included by the tooth 22) of the internal gear 2 reaches each of the outer connecting grooves 6. o The rotation phases of their front ends are different from each other.

[0042] By forming the connecting grooves 6 in this way, such as Figure 5 As shown, in the relationship between the rotational phase of gears 2 and 3 and the total cross-sectional area of ​​each connecting groove 6 surrounding space T, there may be a bending point where, as the rotational phase progresses, the total cross-sectional area continuously increases, and the rate of increase of the total cross-sectional area changes in a stepwise (or discontinuous) manner with the progress of the rotational phase. Specifically, with the rotation of gears 2 and 3, whenever tooth grooves 21 and 31 reach the front end of the connecting groove 6, the total cross-sectional area of ​​each connecting groove 6 surrounding space T increases rapidly.

[0043] Furthermore, the so-called "cross-sectional area of ​​the connecting groove 6 connected to the surrounding space T" refers to the area of ​​the connecting groove 6 when it is connected to the surrounding space T, that is, when the connecting groove 6 crosses the high-pressure region R. H In the state of being separated by teeth 22 and teeth 32 around space T, the flow path cross-sectional area of ​​the groove 6 is connected at the position of tooth surface 2a and tooth surface 3a on the front side of the rotation direction included by the teeth 22 and teeth 32.

[0044] (2) Effects According to the internal gear pump 100 configured in this embodiment, the high-pressure region R is brought into operation as the two gears 2 and 3 rotate. H Multiple connecting slots 6 are formed in ways that differ from the timing of their connection to the space T. Therefore, as the rotational phase advances, the total cross-sectional area of ​​each connecting slot 6 connected to the space T increases whenever the tooth grooves 21 and 31 of gears 2 and 3 reach their respective connecting slots 6. Consequently, as the rotational phase of gears 2 and 3 advances, the total cross-sectional area of ​​the multiple connecting slots 6 connected to the space T continuously increases, and the rate of increase accelerates. Therefore, the amount of working fluid (oil, etc.) introduced from each connecting slot 6 into the tooth grooves 21 and 31 of gears 2 and 3 can be increased more rapidly with rotation. Therefore, compared to existing designs with monotonously shaped connecting grooves (e.g., straight connecting grooves whose cross-sectional area does not change with the advance of the gear's rotational phase, or connecting grooves whose cross-sectional area monotonically increases with the advance of the gear's rotational phase), this design does not significantly advance the timing of pressure rise in tooth grooves 21 and 31 during low rotation of the two gears 2 and 3, but only significantly advances the timing of pressure rise in tooth grooves 21 and 31 during high rotation. Thus, as... Figure 6 As shown, this relates to the space T surrounding the high-pressure region R. H Compared to a single monotonous connecting groove, the internal gear pump 100 and internal gear motor 100 can reduce the deviation in the timing of pressure rise in the grooves 21 and 31 at low and high rotation times, thereby improving pump performance and durability.

[0045] Here, even with multiple conditions surrounding the space T and the high-pressure region R, H In the case of connected slots, for example, Figure 7 As shown, in the high-pressure region R, the rotation of the accompanying gear causes... H Even if the connecting slots are formed in a manner consistent with the timing of the connection around space T, the effect of this embodiment will not be fully realized. That is, in the case described above, such as Figure 8 As shown, when the tooth grooves of the gears reach each connecting groove, the total cross-sectional area of ​​the connecting grooves connected to the space T increases rapidly and continuously with the rotation of the two gears. Thus, as... Figure 9 As shown, compared to the case where there is only one monotonous connecting groove, not only is the timing of the pressure rise in the tooth groove significantly earlier during high rotation, but the timing of the pressure rise in the tooth groove during low rotation is also significantly earlier. As a result, the deviation in the timing of the pressure rise in the tooth groove during low rotation and high rotation cannot be sufficiently reduced, and the pump's performance and durability cannot be fully improved.

[0046] [2] Second implementation form Next, the internal gear pump 100 of the second embodiment of the present invention will be described with reference to the accompanying drawings. Figure 10 As shown, the structure of the internal gear pump 100 in the second embodiment, except for the connecting groove 6, is substantially the same as that in the first embodiment. Hereinafter, the structure of the connecting groove 6 in the internal gear pump 100 of the second embodiment will be described in detail.

[0047] In the second embodiment of the internal gear pump 100, similarly to the first embodiment, the connecting groove 6 is formed such that, as the rotational phase of the two gears 2 and 3 advances, the cross-sectional area communicating with the space T continuously increases, and the rate of increase increases in an accelerating manner.

[0048] Specifically, such as Figure 11 and Figure 12 As shown, a high-pressure region R is formed on the sealing member 5 as a connecting groove 6. H With the inner surrounding space T i Connecting inner groove 6 i and to make the high-voltage region R H Surrounding space T o Connecting outer connecting slot 6 o Inner connecting groove 6 i Connecting groove 6 to the outside o One of each is formed on the sealing member 5. Furthermore, these connecting grooves 6 i 6 o Formed such that, as the rotational phases of the two gears 2 and 3 advance, the inner side surrounds the space T i Reaching the inner connecting groove 6 i The timing and the outer surrounding space T o Reaching the outer connecting slot 6 o The timing was consistent.

[0049] Specifically, the connecting groove 6 is needle-shaped, formed along the side of the sealing member 5. More specifically, the connecting groove 6 is formed such that its base end connects to the high-pressure region R. H The connection port 51 is connected, and its front end tapers as it faces the space T.

[0050] Furthermore, in the internal gear pump 100 of the second embodiment, such as Figure 13 As shown, the connecting channel 6 extends from the high-pressure region R H Oriented towards a cone shape (specifically a pyramid shape) that tapers at the front end around space T, at least one of the plurality of sides 61 of the connecting groove 6 is oriented from the front end side (around space T side) toward the base end side (high pressure region R). HThe connecting groove 6 has a curved shape (R-shape) that gradually expands outward from the front end side. In this embodiment, the connecting groove 6 is a triangular pyramid shape with three sides 61, all of which are curved shapes that expand outward from the front end side towards the base end side. Here, each side 61 is formed to expand outward in a quadratic function form from the front end side towards the base end side. Furthermore, the shape of the connecting groove 6 is not limited to a triangular pyramid shape; for example, it can be a polygonal pyramid shape or a cone shape.

[0051] (2) Effects According to the second embodiment of the internal gear pump 100 configured as described above, the connecting groove 6 extends from the high-pressure region R... H Oriented towards the triangular pyramid shape that tapers at the front end around the space T, the multiple sides 61 of the connecting groove 6 all have a curved shape that expands outward from the front end side towards the base end side, therefore, as Figure 14 As shown, with the forward rotation of the two gears 2 and 3, the cross-sectional area of ​​the connecting groove 6, which communicates with the space T, can be continuously increased, and its rate of increase can be accelerated. As described... Figure 14 As shown, according to the structure of the connecting groove 6 in this embodiment, compared with the existing connecting groove 6 of the first embodiment which only forms a single connecting groove with a monotonous shape, the rate of change (increase rate) of the cross-sectional area of ​​the connecting groove 6 that accompanies the rotation phase of the two gears 2 and 3 can be drastically increased. Therefore, in the internal gear pump 100 of the second embodiment, the amount of working fluid (oil, etc.) introduced from the connecting groove 6 into the tooth grooves 21 and 31 of the gears 2 and 3 can be increased more rapidly with the rotation of the gears 2 and 3. Thus, as... Figure 15 As shown, compared to existing pumps with a single monotonous connecting groove, the timing of pressure rise in the tooth grooves 21 and 31 during low rotation of the two gears 2 and 3 is not significantly advanced, but the timing of pressure rise in the tooth grooves 21 and 31 during high rotation is significantly advanced only. As a result, the internal gear pump 100 of this embodiment can reduce the deviation in the timing of pressure rise in the tooth grooves 21 and 31 during low rotation and high rotation, thereby improving pump performance and durability.

[0052] Furthermore, the second embodiment of the internal gear pump 100, by setting the connecting groove 6 to a pyramidal shape that gradually expands from the front end side towards the base end side, can accelerate the increase rate of the flow path cross-sectional area of ​​the connecting groove 6 that accompanies the rotation of gears 2 and 3 without forming multiple connecting grooves. Therefore, even when it is difficult to form multiple connecting grooves 6 in a limited processing area, forming a single connecting groove 6 can achieve the following effect: the timing of the pressure rise in the tooth grooves 21 and 31 during low rotation of the two gears 2 and 3 is not significantly advanced, but the timing of the pressure rise in the tooth grooves 21 and 31 during high rotation is significantly advanced.

[0053] [3] Other implementation forms Furthermore, the internal gear pump 100 of the present invention is not limited to the embodiments described herein.

[0054] For example, in the internal gear pump 100 of the various embodiments described, one or more connecting grooves 6 are formed on the sealing member 5, but this is not a limitation. In another embodiment, one or more connecting grooves 6 may be formed on the circumferential surface of the filler 4 that contacts the cutting edges of the gears 2 and 3 to seal the tooth grooves 21 and 31. For example, as... Figure 16 As shown, it can be one or more outer connecting slots 6 o From the high-pressure region R H Oriented outward around space T o One or more inner connecting grooves 6 are formed on the outer peripheral surface 41 of the filler 4. i From the high-pressure region R H Oriented inward around space T i It is formed on the inner circumferential surface 42 of the filler 4.

[0055] Additionally, the sealing member 5 in each embodiment includes, but is not limited to, a side plate inserted between the main body 1 and the two gears 2, 3. In another embodiment, the internal gear pump 100 does not include a side plate, and may also function as a sealing member 5 via a front cover 7 and a rear cover 8. In this case, one or more connecting grooves 6 may be formed on the side of the front cover 7 or the rear cover 8 facing the liquid delivery space.

[0056] In another embodiment, the connecting groove 6 only needs to connect the high-pressure region R H If it is connected to the space T, its base end may not be connected to the connection port 51. In addition, the connection port 51 may not be located at the position through which the teeth 22 and teeth 32 of the rotating gears 2 and 3 pass.

[0057] Furthermore, in the first embodiment, the plurality of connecting slots 6 that communicate with each other around the common space T are formed to be generally parallel to each other, but are not limited to this. Additionally, each connecting slot 6 in the first embodiment is not tapered at the front end; for example, it may be rectangular. Furthermore, each connecting slot 6 may be straight or curved.

[0058] Furthermore, in the first embodiment, multiple and identical external connecting slots 6 are formed. o 6 connecting grooves to the inner side i Both parties, but not limited to this. In another embodiment, only the outer connecting slot 6 may be used. o 6 connecting grooves to the inner side i One side has multiple connecting slots 6, while the other side has one or zero connecting slots. Alternatively, there can be multiple outer connecting slots 6.o 6 internal connecting slots i One of them is formed to accompany the rotation of the two gears 2 and 3, causing the high-pressure region R to... H Unlike the timing of connection around space T, another square becomes the high-pressure region R that is affected by the rotation of the two gears 2 and 3. H The timing of the connection with the space T is the same. Alternatively, these connecting slots 6 may not be formed such that, with the rotation of the two gears 2 and 3, the inner side surrounds the space T. i Reaching each inner connecting groove 6 i The timing and the outer surrounding space T o Reaching each outer connecting slot 6 o The timing is consistent. The connecting groove 6 is preferably formed such that the pressure rises at approximately the same time on each of the tooth grooves 21 and 31 during the high and / or low rotation of the two gears 2 and 3.

[0059] Alternatively, in another embodiment of the internal gear pump 100, the connecting groove 6 may be a combination of part or all of the shape of the connecting groove 6 in the first embodiment and part or all of the shape of the connecting groove 6 in the second embodiment. For example, in another embodiment of the internal gear pump 100, a high-pressure region R may be formed that, with the rotation of the two gears 2 and 3, causes the high-pressure region R to be affected. H Multiple connecting channels 6, which connect at different times around space T, are partially or entirely connected from high-pressure region R. H A pyramidal shape that tapers at the front end around a space T, with at least one side having a curved shape that expands outward from the front end side toward the base end side.

[0060] Furthermore, the internal gear pump 100 of each embodiment can also function as an internal gear motor 100 in another embodiment. For example, by introducing working fluid from the suction port P... i The working fluid is introduced into the delivery space, allowing it to flow from the nozzle P. o The ejection can apply rotational torque to the drive shaft 9, which is connected to the rotating shaft of the external gear 3. When functioning as an internal meshing gear motor 100, it interacts with the suction port P in the liquid delivery space. i The connected region becomes the high-voltage region R. H , with the nozzle P o The connected region becomes the low-pressure region R. L That is, when functioning as an internal gear motor 100, the connecting groove 6 is formed to connect the surrounding space T and the low-pressure region R. L The connecting groove 6 is formed such that, as the rotational phase of the two gears 2 and 3 advances, the cross-sectional area connecting to the space T continuously increases, and the rate of increase increases in an accelerating manner. In this case, the connecting groove 6 may also be formed from the high-pressure region R.H The pyramidal shape, tapering towards the front end around the space T, has at least one side 61 that curves outward from the front end towards the base end. Additionally, a plurality of connecting slots 6 are formed to connect the space T with the low-pressure region R. L The interconnected slots 6 are configured to allow the low-pressure region R to rotate with the rotation of the internal gear 2 and the external gear 3. L The timing of connection with space T is different from that of connection.

[0061] [4] The form of the internal gear pump 100 included in this specification Those skilled in the art should understand that the plurality of exemplary embodiments are specific examples of the following forms.

[0062] (First item) One form of the internal gear pump may include: an internal gear rotatably fitted into a body; an external gear internally meshing and engaging with the internal gear; a filler that divides the liquid delivery space formed between the internal gear and the external gear into a high-pressure region and a low-pressure region; and a sealing member that covers both end faces of the two gears in the direction of rotation axis to seal the liquid delivery space, and forms a communication groove for communicating the surrounding space surrounded by the filler and the tooth groove of the at least one gear with the high-pressure region, the communication groove being formed such that the cross-sectional area communicating with the surrounding space continuously increases as the rotation phase of the two gears advances, and the rate of increase increases in an accelerating manner.

[0063] According to the internal gear pump described in the first paragraph, the connecting groove is formed such that its cross-sectional area communicating with the surrounding space continuously increases with the advancement of the rotational phase of the two gears, and the rate of increase increases in an accelerating manner. Therefore, the amount of working fluid (oil, etc.) introduced from the connecting groove into the gear tooth groove can be increased more rapidly with rotation. Thus, the timing of pressure changes in the tooth groove during low rotation of the two gears is not significantly advanced, but the timing of pressure changes in the tooth groove during high rotation is significantly advanced only. Therefore, in the internal gear pump, the deviation in the timing of pressure changes in the tooth groove during low rotation and high rotation can be reduced, improving pump performance and durability. Furthermore, the term "cross-sectional area of ​​the connecting groove" refers to the flow path cross-sectional area of ​​that single connecting groove when there is only one connecting groove communicating with the surrounding space, and the sum of the flow path cross-sectional areas of the multiple connecting grooves when multiple connecting grooves communicating with a common surrounding space are formed.

[0064] (Second item) As a specific form of the internal gear pump according to the first item, the following can be listed: the connecting groove is a pyramidal shape that tapers at the front end from the high pressure area toward the space surrounding it, and at least one side of it is a curved shape that expands outward from the front end side toward the base end side.

[0065] According to the internal gear pump described in the second item, the connecting groove is configured as a pyramidal shape with the sides extending in a curved manner from the front end to the base end. Therefore, as the rotational phase of the two gears advances, the cross-sectional area of ​​the connecting groove communicating with the space around it can be continuously increased, and its rate of increase increases in an accelerating manner.

[0066] Furthermore, according to the internal gear pump described in the second item, even if there is only one connecting groove instead of multiple connecting grooves, the rate of increase in the cross-sectional area of ​​the connecting groove can increase with acceleration as it rotates. Therefore, even if it is difficult to form multiple connecting grooves in a limited processing area, the effect of the internal gear pump described in the first item can be achieved through a single connecting groove.

[0067] (Third item) As a specific form of the internal gear pump according to the second item, the following can be listed: the connecting groove is in the shape of a triangular cone that tapers at the front end from the high pressure area toward the surrounding space, and its three sides are in the shape of a curve that expands outward from the front end side toward the base end side.

[0068] The internal gear pump described in the third item can more significantly enhance the effect of the internal gear pump described in the second item.

[0069] (Fourth item) The internal gear pump according to any one of the first to third items may also be formed with a plurality of the aforementioned connecting slots, wherein the plurality of connecting slots are formed such that the timing of the high-pressure area communicating with the surrounding space is different as the two gears rotate.

[0070] According to the internal gear pump described in the fourth item, multiple connecting slots are formed in such a way that the timing of the high-pressure region's connection with the surrounding space differs with each rotation of the two gears. Therefore, as the rotational phase advances, the total cross-sectional area of ​​each connecting slot connected to the surrounding space T increases each time a gear tooth reaches one of the connecting slots. This allows for a more rapid increase in the amount of working fluid (oil, etc.) introduced from each connecting slot into the gear tooth grooves. Consequently, the timing of the pressure rise in the tooth grooves during low gear rotation does not change significantly, and the timing of the pressure rise in the tooth grooves during high rotation can be further advanced. Thus, in the internal gear pump, the deviation between the timing of the pressure rise in the tooth grooves during low rotation and high rotation can be further reduced.

[0071] (Fifth item) As a specific form of the internal gear pump according to the fourth item, it can be listed that in the relationship between the rotational phase of the two gears and the total cross-sectional area of ​​the connecting grooves that connect the space around it, there is a bending point where, as the rotational phase progresses, the total cross-sectional area increases continuously, and the rate of increase of the total cross-sectional area changes stepwise with the progress of the rotational phase.

[0072] (Sixth) The internal gear pump according to the fourth or fifth item may also include the plurality of connecting slots comprising: a plurality of outer connecting slots connecting the outer surrounding space surrounded by the filling member and the tooth groove of the internal gear to the high-pressure area; and a plurality of inner connecting slots connecting the inner surrounding space surrounded by the filling member and the tooth groove of the external gear to the high-pressure area, wherein the timing of the connection between the high-pressure area and the outer surrounding space is different with the rotation of the two gears, and the timing of the connection between the high-pressure area and the inner surrounding space is different with the rotation of the two gears.

[0073] According to the internal gear pump described in item six, the timing deviation of the pressure rise in the tooth grooves of both the internal and external gears at low and high rotation speeds can be reduced.

[0074] (Seventh) The internal gear pump according to the sixth item may also be configured such that the number of the plurality of inner connecting slots and the plurality of outer connecting slots are the same, and the plurality of inner connecting slots and the plurality of outer connecting slots are formed such that, with the rotation of the two gears, the timing of the inner surrounding space reaching each inner connecting slot is the same as the timing of the outer surrounding space reaching each outer connecting slot.

[0075] According to the internal gear pump described in item 7, the difference in the timing of the pressure rise accompanying rotation in the tooth grooves of the internal and external gears can be reduced.

[0076] (Eighth item) The internal gear pump according to any one of items four to seven may also be such that the plurality of communicating grooves are all of a shape that tapers at the front end from the high-pressure region toward the surrounding space.

[0077] According to the internal gear pump described in item 8, the pressure rise in the surrounding space accompanying rotation can be mitigated, and pressure can be smoothly introduced from the high-pressure area into the surrounding space.

[0078] (Ninth item) The internal gear pump according to any one of the first to eighth items may also be wherein the communicating groove is formed on the sealing member.

[0079] The connecting groove can, for example, be formed on either the sealing member or the filler. The filler often comprises a material with excellent machinability, such as brass, so there is a concern that the connecting groove may be damaged by the pressure of the working fluid when it is formed on the filler. According to the internal gear pump described in claim 9, the connecting groove is formed on a sealing member comprising a material with superior wear resistance compared to the filler, thus suppressing damage to the connecting groove caused by the pressure of the working fluid.

[0080] (Item 10) As a specific form of the internal gear pump according to any one of items 1 to 9, the connecting groove may be formed to connect the high-pressure region with the surrounding space adjacent to the high-pressure region.

[0081] (Eleventh item) As a specific form of the internal gear pump according to any one of the first to tenth items, the connecting groove may be formed in such a way as to span the teeth that separate the high-pressure area from the surrounding space.

[0082] (Item 12) Alternatively, another embodiment of the internal gear motor may include: an internal gear rotatably fitted into a body; an external gear meshing with and engaging the internal gear; a filler that divides the liquid delivery space formed between the internal gear and the external gear into a high-pressure region and a low-pressure region; and a sealing member that covers both end faces of the two gears in the direction of their rotational axes to seal the liquid delivery space, and has a connecting groove for connecting the surrounding space surrounded by the filler and the tooth groove of the at least one gear with the low-pressure region, wherein the connecting groove is formed such that the cross-sectional area communicating with the surrounding space continuously increases as the rotational phase of the two gears advances, and the rate of increase increases in an accelerating manner.

[0083] According to the internal gear motor described in item 12, the connecting groove is formed such that, as the rotational phase of the two gears advances, the cross-sectional area connecting the space continuously increases, and the rate of increase rises with acceleration. Therefore, the amount of working fluid (oil, etc.) discharged from the gear tooth groove to the low-pressure region through the connecting groove can be increased along with the rotational acceleration. Thus, the timing of the pressure reduction in the tooth groove during low rotation of the two gears does not change significantly, but the timing of the pressure reduction in the tooth groove during high rotation can be significantly advanced. Therefore, in the internal gear motor, the deviation between the timing of the pressure reduction in the tooth groove during low rotation and high rotation can be reduced.

[0084] Furthermore, the present invention is not limited to the described embodiments, and various modifications can be made without departing from its spirit.

[0085] [Industry availability] According to the internal gear pump or internal gear motor of the present invention, the timing deviation of pressure changes in the gear grooves during low rotation and high rotation can be reduced.

Claims

1. An internal gear pump, characterized in that, include: The internal gear is rotatably fitted into the main body; The external gear meshes and engages with the internal gear. The filler divides the liquid delivery space formed between the internal gear and the external gear into a high-pressure area and a low-pressure area; as well as A sealing member covers both end faces of the internal gear and the external gear in the direction of their rotation axes, thereby sealing the liquid delivery space. A communication groove is formed to connect the surrounding space, which is surrounded by the tooth grooves of at least one of the filler and the internal gear and the external gear, to the high-pressure area. The connecting groove is formed such that, as the rotational phase of the internal gear and the external gear advances, the cross-sectional area communicating with the surrounding space continuously increases, and the rate of increase rises in an accelerating manner. in, It includes at least one of: a plurality of outer connecting slots that connect the outer surrounding space surrounded by the tooth grooves of the filler and the internal gear to the high-pressure region, and a plurality of inner connecting slots that connect the inner surrounding space surrounded by the tooth grooves of the filler and the external gear to the high-pressure region. At least one of the plurality of outer connecting slots or the plurality of inner connecting slots is configured such that the timing of the connection between the high-pressure region and the surrounding space is different as the internal gear and the external gear rotate.

2. The internal gear pump according to claim 1, characterized in that, The connecting groove is a pyramidal shape that tapers at the front end from the high-pressure area toward the space surrounding it, and at least one side of it has a curved shape that expands outward from the front end side toward the base end side.

3. The internal gear pump according to claim 2, characterized in that, The connecting groove is in the shape of a triangular pyramid that tapers at the front end from the high-pressure area toward the surrounding space, and its three sides are curved and expand outward from the front end to the base end.

4. The internal gear pump according to claim 1, characterized in that, In the relationship between the rotational phase of the internal gear and the external gear and the total cross-sectional area of ​​the connecting groove that connects the space, there exists a bending point where the total cross-sectional area continuously increases as the rotational phase progresses, and the rate of increase of the total cross-sectional area changes in a step-like manner as the rotational phase progresses.

5. The internal gear pump according to claim 1, characterized in that, The plurality of the communicating slots include: The plurality of outer connecting slots connect the outer surrounding space, surrounded by the filling material and the tooth grooves of the internal gear, to the high-pressure area; and The plurality of inner connecting slots connect the inner surrounding space, which is surrounded by the filling material and the tooth grooves of the external gear, to the high-pressure area. The timing at which the high-pressure area connects to the surrounding space differs for each of the aforementioned outer connecting slots, coinciding with the rotation of the internal and external gears. The timing at which the high-pressure area connects with the inner surrounding space is different for each of the inner and outer gears as they rotate.

6. The internal gear pump according to claim 5, characterized in that, The number of the plurality of inner connecting slots and the plurality of outer connecting slots are the same. The plurality of inner connecting slots and the plurality of outer connecting slots are formed such that, with the rotation of the inner gear and the outer gear, the timing at which the inner side reaches each inner connecting slot in the surrounding space coincides with the timing at which the outer side reaches each outer connecting slot in the surrounding space.

7. The internal gear pump according to claim 1, characterized in that, All of the aforementioned connecting slots are shaped to taper at the front end from the high-pressure region toward the surrounding space.

8. The internal gear pump according to any one of claims 1 to 3, characterized in that, The connecting groove is formed on the sealing member.

9. The internal gear pump according to any one of claims 1 to 3, characterized in that, The connecting groove is formed to connect the high-pressure region with the surrounding space adjacent to the high-pressure region.

10. The internal gear pump according to any one of claims 1 to 3, characterized in that, The connecting groove is formed in such a way that it spans the teeth that separate the high-pressure area from the surrounding space.

11. An internal gear motor, characterized in that, include: The internal gear is rotatably fitted into the main body; The external gear meshes and engages with the internal gear. The filler divides the liquid delivery space formed between the internal gear and the external gear into a high-pressure area and a low-pressure area; as well as A sealing member covers both end faces of the internal gear and the external gear in the direction of their rotation axes, thereby sealing the liquid delivery space. A communication groove is formed to connect the surrounding space, which is surrounded by the tooth grooves of at least one of the filler and the internal gear and the external gear, to the low-pressure region. The connecting slot is formed such that, as the rotational phase of the internal gear and the external gear advances, the cross-sectional area communicating with the surrounding space continuously increases, and the rate of increase increases in an accelerating manner. in, It includes at least one of: a plurality of outer connecting slots that connect the outer surrounding space surrounded by the tooth grooves of the filler and the internal gear to the high-pressure region, and a plurality of inner connecting slots that connect the inner surrounding space surrounded by the tooth grooves of the filler and the external gear to the high-pressure region. At least one of the plurality of outer connecting slots or the plurality of inner connecting slots is configured such that the timing of the connection between the high-pressure region and the surrounding space is different as the internal gear and the external gear rotate.

Images