CN2789462Y

CN2789462Y - Gear oil pump

Info

Publication number: CN2789462Y
Application number: CN 200520024055
Authority: CN
Inventors: 陈帮勇
Original assignee: Individual
Current assignee: Min Zongli
Priority date: 2005-05-13
Filing date: 2005-05-13
Publication date: 2006-06-21
Anticipated expiration: 2015-05-13

Abstract

The utility model relates to a gear oil pump belonging to the technical field of the rotary type external gear rotary pump. The utility model aims to provide a gear oil pump which can simplify the hydraulic circuit and has safe and reliable use. The gear oil pump comprises a pump case, a front end cap, a side plate, a driven gear and a driving gear, wherein the rear end of the pump case is integrated with the valve case of the balancing piston type overflow valve; the lower chamber of the main valve of the overflow valve is communicated with the output oil passage of the pump; the oil return channel is arranged between the overflow port and the oil inlet end of the pump. The rear end cap of the existing original gear pump l is omitted, and the rear end of the pump case is integrated with the valve case of an overflow valve so that the gear pump and the overflow valve are integrated. Consequently, not only the structure size of the gear pump is reduced but also the hydraulic circuit is simplified; therefore, the work of the pump is safe and reliable. Simultaneously, the work efficiency and the service life of the pump are respectively enhanced and extended obviously because of the adoption of the flexible side plate. The utility model is an ideal hydraulic element of the mechanical product.

Description

Gear oil pump

Technical field

The utility model relates to a kind of gear oil pump, belongs to rotary type external gear pump technical field.

Background technique

Gear pump is to utilize two or more meshed gears to turn round in pump case, utilize the volume-variation between gear and the pump house wall to carry out work, it is simple in structure, and part is few, particularly requires the part of high-precision processing less, compare with plunger pump with vane pump, advantages such as it is lower to have price, and operational failure is few, it have many uses, with the most use on building machinery and Motor Vehicle, for example be used for the hydraulic power-assisted steering of Motor Vehicle.Its deficiency is when high-pressure work, and the ullage by gear and side plate gap enlarges markedly, performance change, and efficient reduces.For guaranteeing the efficient of pump, adopt floating side plate formula structure more, promptly make axially available mobile lavatory plate, introduce high pressure oil from the side plate back side, when reducing high pressure between sideshake, its working pressure can reach the 10-20 MPa.The pump case two ends of this pump respectively are provided with an end cap, so the pump body structure size is bigger, make processing technology also complicated.In addition,, in oil hydraulic circuit, except relief circuit, also need establish pressure control circuit, promptly adopt relief valve Control work pressure for the safe operation of pump and the working life of prolongation pump.Like this, make the structure of oil hydraulic circuit also seem comparatively complicated.

Summary of the invention

Technical problem to be solved in the utility model provides a kind of safe in utilization, reliable, can simplify the gear oil pump of oil hydraulic circuit.

The alleged problem of the utility model is that following technological scheme solves:

A kind of gear oil pump, it comprises pump case, front cover, side plate, driven gear and driving gear, the valve casing 1 of described pump case 15 rear ends and an equalizing piston formula relief valve is one altogether, the cavity of resorption 2 of relief valve main valve 4 is communicated with the output circuit 18 of pump, is provided with drainback passage between filler opening 14 ends of flow-off 11 and pump.

The said gear oil pump, 8 of the cavity of resorption 2 of described relief valve main valve 4 and pilot valve epicoeles are communicated with damping hole 20, and the sidewall of main valve 4 is provided with the spill port 5 of pilot valve 7.

The said gear oil pump, the described lavatory plate of being located at driving gear 19 and driven gear 13 two ends is a flexible lavatory plate 17.

The said gear oil pump, the hydraulic oil delivery outlet 3 of described output circuit 18 is located on the valve casing 1.

The said gear oil pump, the oral area of described pilot valve epicoele 8 is provided with filter screen.

Gear oil pump provided by the utility model is the improvement on existing rotary type external gear type oil pump basis, the rear end cover of its existing original gear pump saves, the valve casing of a pump case rear end and a relief valve is made as one, make gear pump and relief valve be one altogether, like this, not only dwindled the physical dimension of gear pump, and can simplify oil hydraulic circuit, made the safe and reliable of pump.Simultaneously, the employing of flexible side plate, working efficiency and the working life that can obviously improve pump.The utility model is the desirable hydraulic element of engineering goods.

Description of drawings

Fig. 1 is the A-A sectional view of the utility model Fig. 2;

Fig. 2 is that figure cuts open in the office of overlooking of Fig. 1;

Fig. 3 is that figure cuts open in the left side office of looking of Fig. 1.

The label of each parts is expressed as follows among the figure: 1. valve casing; 2. cavity of resorption; 3. hydraulic oil delivery outlet; 4. main valve; 5. spill port; 6. guide portion spring; 7. pilot valve; 8. pilot valve epicoele; 9. filter screen; 10. main spool spring; 11. flow-off; 12. oil return through-hole; 13. driven gear; 14. filler opening; 15. pump case; 16. front cover; 17. flexible side plate; 18. output circuit; 19. driving gear; 20. damping hole

Embodiment

Below in conjunction with embodiment's accompanying drawing, the utility model is described in further detail:

Referring to accompanying drawing, 15 of the pump cases of gear oil pump that the utility model provides are established front cover 16, and the valve casing 1 of pump case 15 rear ends and an equalizing piston formula relief valve is made as one, and equalizing piston formula relief valve is also referred to as leading role formula relief valve usually.The cavity of resorption 2 of relief valve main valve 4 is communicated with the output circuit 18 of pump, is provided with drainback passage 12 between filler opening 14 ends of flow-off 11 and pump.Be communicated with damping hole 20 between the cavity of resorption 2 of relief valve main valve 4 and the pilot valve epicoele 8, the sidewall of main valve 4 is provided with the spill port 5 of pilot valve 7.

Pilot valve 7 can as shown be steel ball, also can be made into cone valve.The driving gear 19 of pump is flexible side plate 17 with the side plate at driven gear 13 two ends, and flexible side plate 17 is a known prior art.The hydraulic oil delivery outlet 3 of output circuit 18 can be opened on valve casing 1, also can open on pump case 15.In order to make relief valve safe and reliable, the oral area that is preferably in the epicoele 8 of pilot valve 7 is provided with filter screen 9.

The set relief valve of this gear oil pump is identical with the working principle of existing equalizing piston formula relief valve, the damping hole 20 of promptly working as the delivery pressure process main valve 4 of pump passes on the top pilot valve 7, if system pressure surpasses the setting pressure of guide portion spring 6, pilot valve 7 is opened, and pressure oil turns back to filler opening 14 ends of pump through pilot valve epicoele 8, spill port 5, drainback passage 12.Because the damping function of damping hole 20, make 8 of the epicoeles of main valve 4 cavity of resorptions 2 and pilot valve 7 produce pressure difference, make to move on the main valve 4 and open, high pressure oil in the cavity of resorption 2 turns back to filler opening 14 ends of pump through flow-off 11, drainback passage 12, and system pressure reduces, and the pressure of guide portion also descends, therefore, pilot valve 7 is closed, and main valve 4 resets under the effect of main spool spring 10, and each valve is got back to original position and the pressure that keeps setting once more.

Claims

1. gear oil pump, it comprises pump case, front cover, side plate, driven gear and driving gear, it is characterized in that: the valve casing [1] of described pump case [a 15] rear end and an equalizing piston formula relief valve is one altogether, the cavity of resorption [2] of relief valve main valve [4] is communicated with the output circuit [18] of pump, is provided with drainback passage between filler opening [14] end of flow-off [11] and pump.

2. gear oil pump according to claim 1 is characterized in that: be communicated with damping hole [20] between the cavity of resorption [2] of described relief valve main valve [4] and pilot valve epicoele [8], the sidewall of main valve [4] is provided with the spill port [5] of pilot valve [7].

3. gear oil pump according to claim 1 and 2 is characterized in that: the described lavatory plate of being located at driving gear [19] and driven gear [13] two ends is a flexible lavatory plate [17].

4. gear oil pump according to claim 1 and 2 is characterized in that: the hydraulic oil delivery outlet [3] of described output circuit [18] is located on the valve casing [1].

5. gear oil pump according to claim 1 and 2 is characterized in that: the oral area of described pilot valve epicoele [8] is provided with filter screen [9].