Laminated wheel variable pump

Abstract

The utility model belongs to the technical field of variable pumps, and particularly relates to a stacked wheel variable pump which comprises a pump body, an oil inlet and an oil outlet are formed in the end face of the pump body, communicating pipes are arranged on the end face of the oil inlet and the end face of the oil outlet, annular grooves are formed in the inner circle faces of the communicating pipes, and two sealing rings are arranged in the annular grooves. An elastic ring layer is connected between the two sealing rings, a plurality of clamping plates are slidably arranged on one side of the elastic ring layer in the annular groove, a limiting annular groove is formed in the outer circle face of the communicating pipe, a tightening ring with an opening formed in one side is arranged in the limiting annular groove, and a fastening assembly is arranged at the opening of the tightening ring. A clamping linkage assembly is arranged between the tightening ring and the multiple clamping plates. According to the utility model, a plurality of rigid clamps and annular seals can be formed between the external pipeline and the interior of the communicating pipe by screwing a small number of fixing bolts, so that not only is the operation convenient, but also good sealing performance and fastening performance can be ensured, and the stable work of the pump body is ensured.

Description

Technical Field

[0001] The utility model belongs to the technical field of variable pumps, and in particular relates to a folded wheel variable pump. Background Art

[0002] The axial piston constant pressure variable pump can keep the pressure of the hydraulic system constant during operation, and its flow rate can be automatically adjusted according to the load size, effectively reducing the flow loss and achieving the purpose of energy saving and emission reduction. However, the traditional axial piston constant pressure variable pump has many sliding friction pairs and low power-to-weight ratio, which limits its development. For this reason, some domestic scholars continue to deepen their research, and gradually some new piston variable pumps have emerged.

[0003] For example, Zhejiang University of Technology published a paper on the design and research of a stacked two-dimensional (2D) piston constant pressure variable pump. Based on the principle of two-dimensional hydraulics, a stacked two-dimensional piston constant pressure variable pump was designed, and the structural principle verification and corresponding basic research work were carried out. This constant pressure variable pump breaks through the defects of the traditional axial piston constant pressure variable pump, reduces the sliding friction pair, balances the inertial force, is highly integrated in structure, and can connect two pump cores in series to eliminate its structural flow pulsation. Under the same displacement, its volume is smaller, the structure is more compact, and the power-to-weight ratio is greatly improved.

[0004] In the process of continuous research, it is gradually found that the existing two-dimensional piston variable pump still has certain shortcomings:

[0005] 1. Due to the high efficiency of the overall work, the working pressure of the oil outlet and oil inlet pipes is relatively high. Under high-frequency working conditions, gaps and looseness are easily generated at the connections between the oil outlet, oil inlet and external pipelines, causing changes in oil pressure, resulting in poor oil supply and affecting the overall working effect.

[0006] 2. The connection structure between the oil outlet and inlet pipes and the external pipeline is still completed by several bolts and a certain amount of sealant. However, the overall working environment of the variable pump is relatively small and closed, so the connection of the pipeline is inconvenient, resulting in a long overall installation and debugging time, affecting production efficiency. Utility Model Content

[0007] In order to overcome the deficiencies of the prior art, the utility model provides a variable displacement pump with stacked impellers. The utility model is provided with a sealing ring, an elastic ring layer, a fastening assembly, a clamping linkage assembly, etc., so that the staff only needs to insert the external pipe into the interior of the connecting pipe and then turn a small number of fixing bolts to form a plurality of hard clamps and annular seals between the external pipe and the interior of the connecting pipe, which is convenient for operation and can ensure good sealing and fastening, thereby ensuring the stable operation of the pump body.

[0008] In order to achieve the above-mentioned purpose, the utility model provides the following technical solutions: a variable displacement pump with overlapping impellers, comprising a pump body, an oil inlet and an oil outlet are respectively arranged on the end surface of the pump body, a connecting pipe is arranged on the end surface of the oil inlet and the oil outlet, an annular groove is arranged on the inner circumferential surface of the connecting pipe, two sealing rings are arranged in the annular groove, an elastic ring layer is connected and arranged between the two sealing rings, a plurality of clamping plates are arranged on one side of the elastic ring layer for sliding in the annular groove, a plurality of convex strips are arranged on the end surface of each clamping plate close to the elastic ring layer, a limited ring groove is arranged on the outer circumferential surface of the connecting pipe on the outside of the convex strip, a tightening ring with an opening on one side is arranged in the limited ring groove, a tightening assembly is arranged at the opening of the tightening ring, a clamping linkage assembly is arranged between the tightening ring and the plurality of clamping plates, and when the tightening assembly fixes the tightening ring, the clamping linkage assembly drives the clamping plate to move and clamp. Through the arrangement of the sealing ring and the clamping plate, multi-point hard clamping and fixing and annular sealing can be formed on the outside of the external pipe, thereby ensuring the sealing and tightening of the docking.

[0009] Preferably, a plurality of anti-skid grooves are arranged on the inner circumferential surface of the elastic ring layer. The provision of the anti-skid grooves effectively increases the contact friction between the external pipe and the elastic ring layer, thereby improving the fastening performance.

[0010] Preferably, a flange is provided on the upper end surface of the connecting pipe, and a sealing gasket is provided on the end surface of the flange. The arrangement of the flange and the sealing gasket enables the connecting pipe to adapt to the fixed connection mode of the flange.

[0011] Preferably, the fastening assembly includes two connecting plates arranged at both ends of the tightening ring opening, wherein one of the connecting plates is provided with a plurality of connecting holes on its end surface, and the other connecting plate is provided with a plurality of threaded seats coaxial with the connecting holes on its end surface, and fixing bolts are provided in the threaded seats and the connecting holes in cooperation with each other. The arrangement of the threaded seats and the connecting holes enables the staff to complete the fixing of the external pipe by only turning a small number of fixing bolts.

[0012] Preferably, the fastening assembly further comprises anti-skid pads arranged on the adjacent end surfaces of the two connecting plates. The provision of the anti-skid pads improves the overall stability when the two connecting plates abut against each other.

[0013] Preferably, the clamping linkage assembly includes a plurality of sliding inner tubes arranged in the outer circumferential surface of the connecting tube, each of the sliding inner tubes is slidably provided with a push rod, one end of the push rod extends into the annular groove, the end of the push rod extending into the annular groove is connected to the clamping plate, and the other end of the push rod is connected to an abutment rod, and the outer end of the abutment rod contacts the inner circumferential surface of the tightening ring. The arrangement of the push rod and the abutment rod enables the plurality of clamping plates to smoothly complete the clamping and fixing process of the externally connected pipe when the tightening ring is tightened and fixed inwardly.

[0014] Preferably, the clamping linkage assembly further includes a baffle disposed between the abutment rod and the push rod, and a spring is connected between the baffle and the inner end surface of the sliding inner tube. The arrangement of the sliding inner tube and the spring can not only prevent oil leakage but also absorb the vibration generated when the pump body is working, thereby ensuring tightness.

[0015] Preferably, the outer end surface of the abutment rod is in the shape of a semi-arc surface. The arrangement of the abutment rod enables the push rod to be pushed smoothly.

[0016] Preferably, a plurality of vibration detectors are arranged on the outer circumference of the tightening ring. The arrangement of the vibration detectors enables timely inspection of the vibration generated after the tightening ring fixes the external pipe, so that external personnel can understand and deal with it in time.

[0017] In summary, compared with the prior art, the beneficial effects of this solution are:

[0018] (1) The utility model adopts the arrangement of the sealing ring, the elastic ring layer, the clamping plate and the fastening assembly, so that when the external pipe is connected, after the pipe mouth is inserted into the connecting pipe, an annular seal and a hard clamping and fixing treatment at multiple points can be formed outside the external pipe, so that the flow of the entire oil circuit is more stable, and the occurrence of gap leakage and the like is effectively avoided, so that the pump body can stably complete its work.

[0019] (2) The utility model adopts the arrangement of the abutment rod and the clamping linkage assembly, so that when the external pipe is connected, only a small number of fixing bolts need to be turned to complete the rapid fixing and sealing of the external pipe, making the overall operation more convenient, improving the efficiency of installation and maintenance, and improving work efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a three-dimensional diagram of the utility model;

[0021] Figure 2 It is the front view of the utility model;

[0022] Figure 3 It is a side view of the utility model;

[0023] Figure 4 for Figure 2 Stereoscopic cross-sectional view at AA in the middle;

[0024] Figure 5 for Figure 3 A three-dimensional cross-sectional view of the middle BB;

[0025] Figure 6 for Figure 4 A partial enlarged view of point C in the middle;

[0026] Figure 7 for Figure 5 A partial enlarged view of point D in the middle;

[0027] Figure 8 is a three-dimensional diagram of a fastening assembly and a clamping linkage assembly;

[0028] In the figure: pump body 10, oil inlet 11, oil outlet 12, flange 13, sealing gasket 14, tightening ring 15, connecting pipe 16, connecting plate 17, sealing ring 18, annular groove 19, elastic ring layer 20, clamping plate 21, push rod 22, spring 23, sliding inner tube 24, abutment rod 25, anti-skid pad 26, convex strip 27, fixing bolt 28, connecting hole 29, anti-skid groove 30, threaded seat 31, baffle 32, vibration detector 33, limit ring groove 34. DETAILED DESCRIPTION

[0029] In order to enable those skilled in the art to better understand the solution of the present invention, the technical solution in the embodiment of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiment of the present invention.

[0030] Embodiment 1:

[0031] like Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 and Figure 7 As shown, a variable displacement pump with overlapping impellers comprises a pump body 10, on the end surfaces of which an oil inlet 11 and an oil outlet 12 are respectively arranged, and a connecting pipe 16 is arranged on the end surfaces of the oil inlet 11 and the oil outlet 12, and an annular groove 19 is arranged on the inner circumferential surface of the connecting pipe 16, and two sealing rings 18 are arranged in the annular groove 19, and an elastic ring layer 20 is connected and arranged between the two sealing rings 18, and a plurality of clamping plates 21 are slidably arranged in the annular groove 19 on one side of the elastic ring layer 20, and a plurality of convex strips 27 are arranged on the end surface of each clamping plate 21 close to the elastic ring layer 20, and a limiting ring groove 34 is arranged on the outer side of the convex strip 27 on the outer circumferential surface of the connecting pipe 16, and a tightening ring 15 with an opening on one side is arranged in the limiting ring groove 34, and a fastening assembly is arranged at the opening of the tightening ring 15, and a clamping linkage assembly is arranged between the tightening ring 15 and the plurality of clamping plates 21, and when the fastening assembly fixes the tightening ring 15, the clamping linkage assembly drives the clamping plate 21 to move and clamp.

[0032] Specifically, the pump body 10 is a variable pump driven by a two-dimensional pump core. The internal motion structure is the existing technology and will not be elaborated in detail in this scheme. The oil inlet 11 is connected to the oil inlet chamber inside the pump body 10, and the oil outlet 12 is connected to the oil discharge chamber inside the pump body 10. When the pump body 10 is working, the working oil will enter from the oil inlet 11 and be discharged through the oil outlet 12 after completing the working process.

[0033] When the pump body 10 needs to work, the staff can insert the externally connected pipes into the connecting pipes 16 on the end faces of the oil inlet 11 and the oil outlet 12 respectively. The inner wall section of the connecting pipe 16 is stepped, wide at the top and narrow at the bottom, so that one end of the pipe can abut against the stepped surface, thereby ensuring that the external pipe can fully ensure the sealing range and the fixing range. Inside the annular groove 19 arranged on the inner wall of the connecting pipe 16 above the internal step of the connecting pipe 16, there are two sealing rings 18 sealed and filled. The elastic ring layer 20 is connected between the two sealing rings 18, and the sealing ring 18 and the elastic ring layer 20 are connected. 0 are made of elastic sealing rubber material, which is the prior art and will not be elaborated in detail in this solution. The overall thickness of the elastic ring layer 20 is less than that of the sealing ring 18, so that the elastic ring layer 20 has a better elastic deformation effect than the sealing ring 18. The inner circular surface of the sealing ring 18 is provided with a plurality of stripes protruding outward to increase the sealing friction. When the external pipe is inserted into the connecting pipe 16, the external pipe will be squeezed against the inner circular surfaces of the two sealing rings 18, so that the sealing ring 18 as a whole can fully contact with various parts of the outside of the external pipe, thereby ensuring the sealing effect.

[0034] When the external pipe is inserted into the connecting pipe 16, the staff can tighten and fix the tightening ring 15 through the fastening assembly. The tightening ring 15 is made of elastic metal sheet and is slidably embedded in the limiting ring groove 34 when not fastened. When the fastening assembly is tightened, the tightening ring 15 will gradually tighten inward inside the limiting ring groove 34, and the tightening will drive the clamping linkage assembly to work, so that the clamping linkage assembly can push the clamping plate 21 and the multiple convex strips 27 on the end face of the clamping plate 21 to move toward the elastic ring layer 20.

[0035] The clamping plate 21 is in an arc shape as a whole, and basically cooperates with the arc surface of the external pipe. The multiple convex strips 27 can increase the contact friction force on the outside of the clamping plate 21. The clamping plate 21 is located in the gap between the elastic ring layer 20 and the annular groove 19. When the tightening ring 15 is tightened inward, the multiple clamping plates 21 will push the elastic ring layer 20 to move outward, so that the elastic ring layer 20 can form multiple clamping points on the outer circular surface of the external pipe under the pressure of the clamping plate 21. In this relationship, the clamping plate 21 is set on one side of the elastic ring layer 20 to provide clamping pressure when the sealing ring 18 forms a seal, so that the external pipe can be fixed while being sealed, which not only reduces the operation steps but also ensures sealing and tightness.

[0036] Further, such as Figure 7 As shown, a plurality of anti-slip grooves 30 are arranged on the inner circumferential surface of the elastic ring layer 20 .

[0037] Specifically, the plurality of anti-slip grooves 30 are all in a triangular pyramid shape, which can effectively increase the contact friction between the inner circular surface of the elastic ring layer 20 and the outer end surface wall, so that when the clamping plate 21 is pushed outward for clamping, the clamping effect can be improved.

[0038] Further, such as Figure 6 , Figure 7 and Figure 8 As shown, the fastening assembly includes two connecting plates 17 arranged at both ends of the opening of the tightening ring 15, one of the connecting plates 17 is provided with a plurality of connecting holes 29 on the end surface, and the other connecting plate 17 is provided with a plurality of threaded seats 31 coaxial with the connecting holes 29 on the end surface, and the threaded seats 31 and the connecting holes 29 are matched with fixing bolts 28.

[0039] Specifically, when the tightening ring 15 needs to be locked, the staff only needs to rotate the fixing bolt 28 clockwise toward the inside of the threaded seat 31. At this time, the two connecting plates 17 will approach each other, so that the tightening ring 15 can be pulled gradually toward the center of the circle to tighten, and the locking process is completed. In this scheme, a threaded surface is provided on the outside of one end of the fixing bolt 28 that cooperates with the threaded seat 31, so that the fixing bolt 28 can be smoothly screwed into the threaded seat 31. When screwing in, spring washers and other items can also be placed on the nut end of the fixing bolt 28. These are all prior arts, and this scheme will not be elaborated in detail. At the same time, the number of the threaded seat 31 and the fixing bolt 28 is not excessively limited. The staff can make adaptive changes according to the width or length of the connecting plate 17, and this scheme will not be elaborated in detail. The above scheme allows the staff to insert the external pipe into the connecting pipe 16, and then rotate a few fixing bolts 28 to complete effective fixing and sealing, which effectively improves the convenience of operation.

[0040] Further, such as Figure 6 , Figure 7 and Figure 8 As shown, the clamping linkage assembly includes a plurality of sliding inner tubes 24 arranged in the outer circumferential surface of the connecting tube 16, and a push rod 22 is slidably arranged in each sliding inner tube 24. One end of the push rod 22 extends into the annular groove 19, and one end of the push rod 22 extending into the annular groove 19 is connected to the clamping plate 21, and the other end of the push rod 22 is connected to an abutment rod 25, and one end of the outer side of the abutment rod 25 contacts the inner circumferential surface of the tightening ring 15.

[0041] Specifically, multiple sliding inner tubes 24 are arranged on the outer circumferential surface of the connecting tube 16 on one side of the clamping plate 21, and both sides of the sliding inner tube 24 are through holes, so that the push rod 22 can smoothly extend into the annular groove 19 and connect with the clamping plate 21. The abutment rod 25 at the other end of the push rod 22 extends out of the sliding inner tube 24 and abuts against the inner circumferential surface of the tightening ring 15. When the tightening ring 15 is gradually tightened inwardly, the tightening ring 15 gathered toward the center of the connecting tube 16 will push the abutment rod 25 and the push rod 22 at one end of the abutment rod 25 to move inward, thereby pushing the clamping plate 21 at one end of the push rod 22 to clamp and fix the elastic ring layer 20 and the external pipe on one side of the elastic ring layer 20. In this scheme, a sealing structure is provided on the outside where the push rod 22 passes through the connecting tube 16 and is connected to the clamping plate 21. The specific sealing structure is a prior art and will not be elaborated in this scheme. It ensures that the push rod 22 can slide smoothly while avoiding leakage.

[0042] Further, such as Figure 6 , Figure 7 and Figure 8 As shown, the clamping linkage assembly further includes a baffle plate 32 disposed between the abutment rod 25 and the push rod 22 , and a spring 23 is connected between the baffle plate 32 and the inner end surface of the sliding inner tube 24 .

[0043] Specifically, the outer circumferential surface of the baffle 32 and the inner circumferential surface of the sliding inner tube 24 are piston-type matched to ensure the sliding stability of the push rod 22 while ensuring the sealing effect. The spring 23 connected between the baffle 32 and the inner end surface of the sliding inner tube 24 can be deformed under pressure when the tightening ring 15 is clamped to fix the external pipe, and can absorb certain vibrations when the pump body 10 is working to ensure the tightening effect. When the tightening ring 15 is loosened, the spring 23 can push the baffle 32 outward and the clamping plate 21 on one side of the baffle 32 to loosen the clamping, so that the external pipe can be smoothly pulled out, improving the convenience of operation.

[0044] Further, such as Figure 3 As shown, a plurality of vibration detectors 33 are arranged on the outer circumferential surface of the tightening ring 15 .

[0045] Specifically, the vibration detector 33 is a prior art and will not be elaborated in detail in this solution. The vibration detector 33 is attached to the outside of the tightening ring 15. When the oil outlet 12 or the oil inlet 11 is working, the vibration can be detected, so that external personnel can promptly judge the fixing effect of the connecting tube 16 on the external pipeline, so that the oil can flow smoothly, reduce vibration, and ensure the stable operation of the pump body 10.

[0046] Embodiment 2:

[0047] like Figure 1 As shown, a variable displacement pump with overlapping impellers has a flange 13 disposed on the upper end surface of a connecting pipe 16 , and a sealing gasket 14 disposed on the end surface of the flange 13 .

[0048] As a further embodiment, when there is a flange fixing surface on the external pipe, the staff can fit the flange surface of the external pipe on the end face of the flange 13, and then connect and fix it through multiple bolts. The sealing gasket 14 on the end face of the flange 13 is provided with multiple anti-slip stripes on the end face, and the flange 13 and the flange surface of the external pipe can be sealed to ensure the quality of sealing and fixing. In this solution, through the provision of the flange 13, the connecting pipe 16 can better adapt to different connection environments.

[0049] Embodiment three:

[0050] like Figure 7 As shown, in a variable displacement pump with overlapping impellers, the fastening assembly further includes anti-skid pads 26 arranged on adjacent end surfaces of the two connecting plates 17 .

[0051] As a further embodiment, the provision of the anti-slip pad 26 can effectively improve the contact friction between the two connecting plates 17, so that after the two connecting plates 17 are fitted together, the overall anti-slip and fixing stability can be effectively improved, so that the overall fastening quality can be guaranteed.

[0052] Embodiment 4:

[0053] like Figure 6 and Figure 7 As shown, a variable displacement pump with overlapping impellers has an outer end surface of the abutment rod 25 in the shape of a semi-arc surface.

[0054] As a further embodiment, the outer end surface of the abutment rod 25 is in a semi-arc shape and abuts against the inner circular surface of the tightening ring 15. The setting of the semi-arc surface can reduce the jamming of the abutment rod 25 when the tightening ring 15 is tightened, so that the abutment rod 25 and the push rod 22 can be pushed inward smoothly to ensure the fixing efficiency.

[0055] For example, certain words are used in the specification and claims to refer to specific components. Those skilled in the art will understand that hardware manufacturers may use different terms to refer to the same component.

[0056] The requirement is not to distinguish components by name, but by functional differences. As mentioned in the specification and claims, "including" is an open term and should be interpreted as "including but not limited to". "Substantially" means that within an acceptable error range, a person skilled in the art can solve the technical problem within a certain error range and basically achieve the technical effect.

[0057] It should be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a product or system including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such product or system. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the product or system including the elements.

[0058] The above description shows and describes several preferred embodiments of the present application, but as mentioned above, it should be understood that the present application is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the application concept described herein through the above teachings or the technology or knowledge of the relevant field. The changes and modifications made by those skilled in the art do not deviate from the spirit and scope of the present application, and should be within the scope of protection of the claims attached to the present application.

Claims

1. A variable displacement pump comprising a pump body (10), characterized in that: An oil inlet (11) and an oil outlet (12) are respectively arranged on the end surface of the pump body (10), and a connecting pipe (16) is arranged on the end surface of the oil inlet (11) and the oil outlet (12). An annular groove (19) is arranged on the inner circumferential surface of the connecting pipe (16), and two sealing rings (18) are arranged in the annular groove (19). An elastic ring layer (20) is connected between the two sealing rings (18), and a plurality of clamping plates (21) are slidably arranged on one side of the elastic ring layer (20) in the annular groove (19), and each of the clamping plates (21) A plurality of convex strips (27) are arranged on the end surface close to the elastic ring layer (20); a limiting ring groove (34) is arranged on the outer circumferential surface of the connecting tube (16) on the outside of the convex strip (27); a tightening ring (15) with an opening on one side is arranged in the limiting ring groove (34); a fastening component is arranged at the opening of the tightening ring (15); a clamping linkage component is arranged between the tightening ring (15) and the plurality of clamping plates (21); when the fastening component fixes the tightening ring (15), the clamping linkage component drives the clamping plate (21) to move and clamp.

2. A variable displacement pump according to claim 1, characterized in that: The upper end surface of the connecting pipe (16) is provided with a flange (13), and the end surface of the flange (13) is provided with a sealing gasket (14).

3. A variable displacement pump according to claim 1, characterized in that: The fastening assembly comprises two connecting plates (17) arranged at both ends of an opening of a tightening ring (15), wherein a plurality of connecting holes (29) are arranged on an end surface of one of the connecting plates (17), and a plurality of threaded seats (31) coaxial with the connecting holes (29) are arranged on an end surface of the other connecting plate (17), and fixing bolts (28) are arranged in cooperation with the threaded seats (31) and the connecting holes (29).

4. A variable displacement pump according to claim 3, characterized in that: The fastening assembly also includes an anti-slip pad (26) arranged on adjacent end surfaces of the two connecting plates (17).

5. The variable displacement pump according to claim 1, characterized in that: The clamping linkage assembly comprises a plurality of sliding inner tubes (24) arranged in the outer circumferential surface of the connecting tube (16), each of the sliding inner tubes (24) being provided with a push rod (22) for sliding, one end of the push rod (22) extending into the annular groove (19), one end of the push rod (22) extending into the annular groove (19) being connected to the clamping plate (21), and the other end of the push rod (22) being connected to an abutment rod (25), one end of the abutment rod (25) being in contact with the inner circumferential surface of the tightening ring (15).

6. A variable displacement pump according to claim 5, characterized in that: The clamping linkage assembly also includes a baffle (32) arranged between the abutment rod (25) and the push rod (22), and a spring (23) is connected between the baffle (32) and the inner end surface of the sliding inner tube (24).

7. A variable displacement pump according to claim 5, characterized in that: The outer end surface of the abutment rod (25) is in the shape of a semi-arc surface.

8. The variable displacement pump according to claim 1, characterized in that: A plurality of vibration detectors (33) are arranged on the outer circumferential surface of the tightening ring (15).

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