CN200996376Y - Low-noise gear oil pump - Google Patents

Abstract

A silent gear oil pump is characterized in that two front and back gear cavities along the axial direction are provided on a same pump body (6), including a front gear cavity (10) and a back gear cavity (11); the front gear cavity (10) is connected with the back gear cavity (11), the two gear cavities are respectively provided with one gear pair, and two gear pairs are linked in coaxial mode and deflect semi-pitch on the circle.

Description

Gear oil pump with low noise

Technical field

The present invention relates to gear oil pump, more specifically say so, be particularly useful for electronic haulage equipment as the hydraulic gear oil pump of hydraulic system dynamical element.

Technical background

Gear oil pump is widely used in the hydraulic system of engineering machinery such as fork truck, loader, excavator, hoist as the dynamical element of hydraulic system.The general work place is not high to the gear oil pump noise requirements in the hydraulic system, and the noise figure of regulation is 85dB in JB/T7041-1993 " hydraulic gear pump technical specifications " _(A)(10～25MPa, discharge capacity is 10～50mL/r).But in some special operational sites, require the gear oil pump in the hydraulic system that lower noise figure is arranged, on the main frames such as Electric Fork Lift Trucks that use in the storage, room noise requires to be lower than 74dB _(A)Progress along with science and technology, the raising of people's environmental consciousness, all have higher requirement to the reduction noise of gear pump in increasing operational site, for some electronic haulage equipments, because design of Hydraulic System compactness, thereby system works oil is warm than higher, and general proper functioning oil temperature just between 90 ℃～100 ℃, exceeds a lot for warm 50 ℃～60 ℃ than common hydraulic system oil.

Hydraulic gear oil pump for conventional design, because its intrinsic structure characteristic, having determined noise of gear pump to produce has its main several aspects, and the one, the mechanical transmission noise that gear meshing produced, this noise like can reduce by improving the Gear Processing precision; The 2nd, the pocketed oil noise, this depends on the design of offering of gear pump drain charge groove and gear parameter; The 3rd, the noise that flow pulsation produces, for the fixing gear pump of the number of teeth, its flow pulsation coefficient is bigger.In addition, the reason that produces of noise of gear pump is also relevant with the material of the pump housing of gear pump and axle sleeve or side plate.At high temperature the common aluminum of hydraulic gear pump, copper, bimetallic material axle sleeve or side plate are the internal cause that causes the gear pump operating life short owing to many-sided reasons such as its processing and service conditions.

The model utility content

The utility model is for fear of above-mentioned existing in prior technology deficiency, and a kind of gear oil pump with low noise that especially can effectively reduce the flow pulsation noise is provided.

The utility model technical solution problem adopts following technological scheme.

Structural feature of the present utility model is: on the same pump housing, two gear cavities one in front and one in back are set vertically, comprise front gear chamber and backgear chamber, front gear chamber and backgear chamber are interconnected, one group of gear pair respectively is set in two gear cavities, coaxial interlock between two groups of gear pairs, and upward deflecting half tooth pitch week.

Structural feature of the present utility model also is:

Gear in each gear pair adopts the double modulus asymmetric tooth, and asymmetric tooth is between a pair of intermeshing gear teeth, is on its non-working surface, is formed with the cavity that increases protected oil volume.

Pump housing side plate adopts the powdered metallurgical material pressboard, and the pump housing is a nodular iron casting.

Compared with the prior art, the beneficial effects of the utility model are embodied in

1, the utility model bidentate wheel set the flow pulsation coefficient that can effectively reduce gear pump is set, and then reduce the flow pulsation noise.

2, the utility model adopts asymmetric special tooth profile gear pair, increases the cavity of protected oil volume, not only effectively reduces the pocketed oil noise of gear transmission noises and gear pump, has also reduced the radial dimension of gear pump simultaneously significantly.

3, the utility model adopts the pump housing side plate of high-strength powder metallurgy material compacting, higher properties of antifriction and wear resistance and certain damping noise reduction level are arranged, effectively improve the side plate precision, reduce the side plate difficulty of processing, prolong the working life of gear pump, satisfy the usability requirement of gear pump under high temperature, high pressure.

4, the utility model is as a kind of environment protection type gear oil pump, the global design compactness, and beautiful shape is generous.

Description of drawings

Fig. 1 is the utility model structural representation.

Fig. 2 (a) is the utility model asymmetric tooth structural representation.

Fig. 2 (b) is the utility model shaft extension end view.

Fig. 2 (c) is the utility model internal structure schematic representation.

Fig. 2 (d) is the A-A cross-sectional schematic of Fig. 2 (b).

Fig. 3 (a) is the utility model unsymmetric gear engagement schematic representation.

Fig. 3 (b) is symmetrical gear engagement states schematic representation.

Fig. 4 is the utility model lateral plate structure schematic representation.

Fig. 5 is that the not inclined to one side tooth of two groups of gears of bidentate wheel set is installed the flow pulsation oscillogram.

Fig. 6 is that inclined to one side half tooth of two groups of gears of the utility model bidentate wheel set is installed the flow pulsation oscillogram.

Fig. 7 is asymmetric tooth and symmetrical profile of tooth flow curve figure.

Number in the figure: driving gear, 2 preceding driven gears, 3 protecgulums, 4 pump housing side plates, 5 back driven gears, 6 pump housings, 7 rear drive gears, 8 bearings, 9 bonnets, 10 front gear chambeies, 11 backgear chambeies, 12 cavitys, 13 non-working surfaces, 14 working surfaces, 15 symmetrical gears, 16 unsymmetric gears before 1.

Below pass through embodiment, and in conjunction with the accompanying drawings the utility model be further described:

Embodiment

Referring to Fig. 1, Fig. 2 (b), Fig. 2 (c) and Fig. 2 (d), on the same pump housing 6, two gear cavities one in front and one in back are set vertically, be front gear chamber 10 and backgear chamber 11, one group of gear pair respectively is set in two gear cavities, the i.e. one group of gear pair that constitutes by preceding driving gear 1 and preceding driven gear 2, and another group gear pair that constitutes by moving driving gear 7 in back and back driven gear 5, be coaxial interlock between preceding driving gear 1 and rear drive gear 7, two groups of gear pairs are upward deflecting half tooth pitch week.

Be provided with routinely, the front-end and back-end of the pump housing 6 are set to protecgulum 3 and bonnet 9 respectively, and gear shaft bearing 8 is set in bonnet 9.

In order further to reduce noise, increase the service life, improve functional reliability, also comprise in concrete the enforcement:

Shown in Fig. 2 (a), Fig. 3 (a), gear in the present embodiment in each gear pair adopts the double modulus asymmetric tooth, and gear tooth simultaneously is a working surface 14, and another side is a non-working surface 13, on the non-working surface 13 of gear tooth, cut out one, form the cavity 12 on the non-working surface 13.This structure setting makes the unsymmetric gear protected oil volume V1 of gear pump increase to some extent with respect to symmetrical gear protected oil volume V2, but gear is when engagement, relative the reducing of difference Δ V of the maximum volume V1 in pocketed oil district and minimum volume, final protected oil volume changes less relatively, and noise figure is descended to some extent.Such as, not clocking to ignoring when Δ V is little with respect to V1 or V2, gear pump is also just never at the pocketed oil noise.Fig. 3 (a) is depicted as the engagement schematic representation between the unsymmetric gear 16 in the present embodiment.Fig. 3 (b) is the engagement schematic representation between the symmetrical gear 15.

Common bimetal lateral plate structure complexity, require very high to dimensional accuracy and surface finishment, thereby, the manufacturing of bimetal side plate has certain degree of difficulty, precision is low, manufacture cycle is long, the processing charges height, especially high pressure, under the high temperature condition, stuck because of expansion easily, lubrication antifriction decreased performance, wearing and tearing aggravation, working efficiency reduces, satisfy to install and have only the expansion matching gap, side plate forms couple easily in gear cavity like this, and this will aggravate the wearing and tearing of side plate, simultaneously, at high temperature the sinter layer of bimetal side plate peels off easily and will have a strong impact on the working life of gear pump.Pump housing side plate 4 in the present embodiment adopts the high-strength powder metallurgy material pressboard, the powdered metallurgical material side plate has higher properties of antifriction and wear resistance and certain damping noise reduction level, effectively improved the precision of side plate, reduced the difficulty of processing of side plate, prolong the working life of gear pump, satisfied the usability requirement of gear pump under high temperature, high pressure.

The pump housing 6 in the present embodiment can adopt nodular iron casting, has certain damping noise reduction performance, the intensity height, and wear-resisting property is good, has effectively improved the bearing capacity of pump, prolongs the working life of pump.

In addition, the setting of conventional bidentate wheel set gear pump is that one or two transition joining plate will be arranged between the pump of front and back, and the setting of transition joining plate causes volume big, and sealing part is more.Forward and backward gear chamber is placed on the same pump housing in the present embodiment, can omit the joining plate between the forward and backward pump like this, can reduce the axial dimension of gear pump significantly, reduces the sealing part of gear pump, reduces the possibility that leaks outside.

Present embodiment is by the ripple factor that reduces gear pump, the asymmetric tooth gear pair that adopts correction, the noise of gear pump is reduced from several main generation links such as pulsation, mechanical transmission, pocketed oil significantly, noise figure is controlled in about (72 ± 2) dB (A), product has the excellent properties that satisfies 90 ℃～100 ℃ following long-time proper functioning of high temperature, be the green design design for environment of gear pump, have certain environment protection significance.

Figure 5 shows that the not inclined to one side half tooth installation of two groups of gears of bidentate wheel set flow pulsation oscillogram, Figure 6 shows that the inclined to one side half tooth installation of two groups of gears of bidentate wheel set flow pulsation oscillogram.Relatively as seen, adopt the installation form of two groups of inclined to one side half teeth of gear of bidentate wheel set can reduce flow pulsation greatly.

Y coordinate Q is an instantaneous flow among Fig. 7, and abscissa n is a revolution, and curve a is that asymmetric tooth flow curve, curve b are symmetrical profile of tooth flow curve.

Concrete enforcement axis stretched form is various, the gear cavity of two gear pairs is placed on the same pump housing 6, the pump housing 6 and bonnet 9 all can be processed hydraulic fluid port, pump housing hydraulic fluid port can be divided into flange and thread forms, make this pump Placement realize variation, the user uses more convenient, satisfies multi-user's requirement, the utility model can be processed hydraulic fluid port respectively with this pump according to customer requirements on the pump housing 6 and bonnet 9, the front and back gear cavity is not linked up and be can be used as the duplex pump use.

Claims (3)

1, gear oil pump with low noise, it is characterized in that on the same pump housing (6), two gear cavities one in front and one in back are set vertically, comprise front gear chamber (10) and backgear chamber (11), front gear chamber (10) is interconnected with backgear chamber (11), one group of gear pair respectively is set in two gear cavities, coaxial interlock between two groups of gear pairs, and upward deflecting half tooth pitch week.

2, gear oil pump with low noise according to claim 1, it is characterized in that the gear in described each gear pair adopts double modulus asymmetric tooth (16), described asymmetric tooth (16) is between a pair of intermeshing gear teeth, be on its non-working surface (13), be formed with the cavity (12) that increases protected oil volume.

3, gear oil pump with low noise according to claim 1 is characterized in that described pump housing side plate (4) adopts the powdered metallurgical material pressboard, and the described pump housing (6) is a nodular iron casting.

Images