External gear pump capable of compensating end surface clearance
Technical Field
The utility model relates to a gear pump specifically relates to an external gear pump that can compensate end clearance belongs to mechanical equipment technical field.
Background
The leakage of the gear pump at present mainly has three forms: the end face leakage exists, a gap exists between the end face of the gear and the cover plate, the main leakage form of the gear pump is realized, and the leakage form accounts for about 70-80 percent; secondly, radial leakage exists, and a gap exists between the top circle of the gear teeth and the inner cavity of the shell; thirdly, the meshing part leaks, and a small amount of leakage exists at the meshing part of the two gears; in general, a gap is left between a cover plate and a gear of the gear pump to satisfy the lubrication required during the rotation of the gear, and at the same time, a part of pressure oil of an oil outlet leaks to an oil inlet cavity from the gap to cause the reduction of volumetric efficiency, so that the reduction of the leakage of the end face of the gear is urgent for improving the volumetric efficiency of the gear pump.
SUMMERY OF THE UTILITY MODEL
The utility model aims at providing a to the not enough of prior art existence, provide a machining degree of difficulty little, with low costs, the volume is efficient can compensate end clearance's external gear pump.
In order to realize the above-mentioned purpose, the utility model provides a can compensate end clearance's external gear pump, be in including the pump body and setting die cavity in the pump body, the top of the pump body is provided with the pump cover, be provided with the driving gear in the die cavity, the meshing has driven gear on the driving gear, install the drive shaft on the mounting hole of driving gear, install on driven gear's the mounting hole by the drive shaft, the driving gear with driven gear's upper surface is provided with unsteady cover, unsteady sheathe in and is provided with the special-shaped sealing washer, unsteady cover with fix a position through the outer lane between the pump body, the pump cover is arranged in unsteady top of overlapping.
As a further improvement of the scheme, the floating sleeve is provided with a sealing groove, and the sealing groove is matched with the special-shaped sealing ring.
As a further improvement of the scheme, the outer contour of the floating sleeve is in an 8 shape, and two oil grooves are formed in the outlet side of the floating sleeve.
As a further improvement of the scheme, the floating sleeve is provided with two inner holes which are respectively sleeved with the driving shaft and the driven shaft, and the driving shaft, the driven shaft and the inner holes are in clearance fit.
As a further improvement of the scheme, the floating sleeve axially floats in the cavity of the pump body.
As a further improvement of the scheme, the pump cover is connected with the pump body through a plurality of groups of nuts and bolts in a matched mode.
As a further improvement of the scheme, the floating sleeve is made of one of aluminum alloy, powder metallurgy and plastics.
The utility model has the advantages that: the floating sleeve adopted by the external gear pump capable of compensating the end surface clearance has low requirement on the size of an inner hole, small machining difficulty and low cost by setting a large clearance between the inner hole of the floating sleeve and a driven shaft of a driving shaft, and the inner hole of the floating sleeve does not play a role of a bearing; compared with the floating sleeve made of aluminum alloy, the floating sleeve made of powder metallurgy or plastic is formed by an integral die, the outer ring, the inner hole and the special-shaped sealing ring do not need to be processed, only the upper surface and the lower surface of the floating sleeve need to be processed, the machining characteristics are further reduced, and the cost is reduced; two small oil grooves are designed on the outlet side of the floating sleeve, high-pressure oil can easily enter the sealing groove area to perform pressure compensation, so that the floating sleeve can better stick to the driving gear and the driven gear, and leakage is reduced; the sealing ring in the utility model has the characteristic of fixing bulge, so as to fix the sealing ring and be easy to assemble; the floating sleeve and the sealing ring can also be manufactured into a part by adopting a secondary forming process; the volume efficiency can reach 90 percent, and the mechanical efficiency reaches 80 percent.
Drawings
Fig. 1 is a schematic structural diagram of an external gear pump capable of compensating for an end face clearance according to an embodiment of the present invention;
fig. 2 is a sectional view taken along the line a-a in fig. 1.
The parts of the drawings are numbered as follows: a pump body 1; a pump cover 2; a driving gear 3; a driven gear 4; a drive shaft 5; a driven shaft 6; a floating sleeve 7; a special-shaped sealing ring 8; a seal groove 9; an oil sump 10.
Detailed Description
In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the drawings of the embodiments of the present invention are combined below to clearly and completely describe the technical solution of the embodiments of the present invention. It is to be understood that the embodiments described are only some of the embodiments of the present invention, and not all of them. All other embodiments, which can be derived from the description of the embodiments of the present invention by a person skilled in the art, are within the scope of the present invention.
Example 1
As shown in fig. 1 and 2, an external gear pump capable of compensating for end face clearances comprises a pump body 1 and a cavity arranged in the pump body 1, wherein a pump cover 2 is arranged at the top end of the pump body 1, a driving gear 3 is arranged in the cavity, a driven gear 4 is meshed on the driving gear 3, a driving shaft 5 is arranged on a mounting hole of the driving gear 3, a driven shaft 6 is arranged on a mounting hole of the driven gear 4, a floating sleeve 7 is arranged on the upper surfaces of the driving gear 3 and the driven gear 4, a special-shaped sealing ring 8 is arranged on the floating sleeve 7, the floating sleeve 7 and the pump body 1 are positioned through an outer ring, the pump cover 2 is arranged above the floating sleeve 7, and the pump cover 2 and the pump body 1 are connected through a plurality of nut-bolt matching.
As shown in fig. 2, a sealing groove 9 is formed in the floating sleeve 7, the sealing groove 9 is matched with the special-shaped sealing ring 8, the outer contour of the floating sleeve 7 is 8-shaped, the floating sleeve 7 axially floats in the cavity of the pump body 1, two oil grooves 10 are formed in the outlet side of the floating sleeve 7, pressure oil can conveniently flow into the sealing groove 9 through the oil grooves 10 in the floating sleeve 7, the floating sleeve 7 is tightly attached to the surfaces of the driving gear 3 and the driven gear 4, and meanwhile, the special-shaped sealing ring 8 can also provide downward pre-pressure, so that the influence of the end face gap on the oil pump is furthest compensated.
In this embodiment, two inner holes are formed in the floating sleeve 7, the driving shaft 5 and the driven shaft 6 are sleeved on the floating sleeve 7 respectively, the driving shaft 5 and the driven shaft 6 are in clearance fit with the inner holes, the clearance at the position is set to be a large clearance, namely the inner hole of the floating sleeve 7 does not play a role of a bearing, so that the requirement on the inner hole of the floating sleeve 7 is not high, the machining difficulty and cost are greatly reduced, in addition, the floating sleeve 7 is arranged on the driving gear 3 and the upper surface structure of the driven gear 4, and the assembly is also easy.
In this embodiment, the cover 7 that floats is one of aluminum alloy, powder metallurgy and plastics, and during mass production, preferentially adopt powder metallurgy or plastics the cover 7 that floats produces, these two kinds of materials the cover 7 that floats can adopt the mould shaping to come out, and machining only need right the cover 7 upper and lower surface that floats processes can, effectively reduces the machining beat, reduce cost.
In summary, according to the above embodiment, the floating sleeve adopted by the external gear pump capable of compensating the end face clearance has the advantages that the floating sleeve is provided with the large clearance between the inner hole of the floating sleeve and the driven shaft of the driving shaft, and the inner hole of the floating sleeve does not play a role of a bearing, so that the requirement on the size of the inner hole is not high, the machining difficulty is small, and the cost is low; compared with the floating sleeve made of aluminum alloy, the floating sleeve made of powder metallurgy or plastic is formed by an integral die, the outer ring, the inner hole and the special-shaped sealing ring do not need to be processed, only the upper surface and the lower surface of the floating sleeve need to be processed, the machining characteristics are further reduced, and the cost is reduced; two small oil grooves are designed on the outlet side of the floating sleeve, high-pressure oil can easily enter the sealing groove area to perform pressure compensation, so that the floating sleeve can better stick to the driving gear and the driven gear, and leakage is reduced; the sealing ring in the utility model has the characteristic of fixing bulge, so as to fix the sealing ring and be easy to assemble; the floating sleeve and the sealing ring can also be manufactured into a part by adopting a secondary forming process; the volume efficiency can reach 90 percent, and the mechanical efficiency reaches 80 percent.
It is obvious to a person skilled in the art that the invention is not restricted to details of the above-described exemplary embodiments, but that it can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.
Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.