JPS6026187A - Pump system - Google Patents

Abstract

PURPOSE:To reduce cost without requiring special sealing structure by providing a relief valve for returning the delivery oil from a pump to the oil reservoir side on the side face arranged in an oil reservoir of pump body thereby preventing oil leakage. CONSTITUTION:A relief valve 50 for returning the excessive oil to the oil reservoir side 15 when the pressure of delivery oil from a pump 11 exceeds over the setting level is provided on a side face arranged in the oil reservoir 15 of pump body 12. A plug body assembled of a ball 52a, ball stopper 52b, valve seat 52c and spring 52d, etc. for forming the relief valve 50 is screwed from the pump body 12 side to a path hole 51 made to open toward the delivery side path hole 32 of pump 11. Consequently, the oil leakage is prevented while the seal structure is eliminated, to reduce the cost and to make the pump compact.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to improvements in pump devices that serve as oil pressure generation sources in various hydraulic equipment and devices.

[Prior art]

Generally, this type of pump device includes a pump that sucks in and discharges hydraulic oil, a suction valve and a discharge valve that form a pump chamber, and a suction boat into which the hydraulic oil flows, and a discharge boat via the pump chamber. Equipped with suction and discharge side passages,
These are integrally formed within the pump body. In addition, a relief pulp or the like is attached to the pump body to appropriately recirculate a part of the oil to the pump suction side in order to control the oil discharged from the pump to a predetermined amount (or predetermined pressure). A pump device having a structure in which an oil reservoir or the like for storing hydraulic oil is integrally attached to one side is also known.

By the way, in the above-mentioned pump device, the relief pulp that recirculates a part of the oil discharged from the pump to the pump suction side has conventionally been connected to the internal discharge side passage from the outer surface of the pump body through a small diameter hole. A pulp hole formed so as to open, a ball that is pressed against a valve seat at the bottom by a spring or the like and opens and closes this part at a desired set pressure, and a plug that closes the open end of the pulp hole. It was constructed of a reflux passage that opened into the valve hole and was connected to a pump suction side passage or an oil reservoir.

In such a conventional structure, the plug that closes the opening end of the valve hole has the function of adjusting the set pressure as a relief pulp, and at the same time has a sealed plug structure that prevents oil leakage from this part. However, it lacks reliability in terms of oil tightness, and in order to prevent this, a special seal structure is required for this plug part, which is complicated and leads to high costs. is occurring.

In addition, in the above-mentioned structure in which the relief valve is mounted from the outside of the pump body, a part of the relief valve protrudes outward, which is a problem in making the pump smaller and more compact. It is hoped that it will be resolved.

[Summary of the invention]

The present invention was made in view of these circumstances.
With a simple configuration, a relief valve that recirculates the oil discharged from the pump according to the set pressure is attached to the side of the pump body located inside the oil reservoir.
There is no need to worry about oil leakage, which is a problem when the relief valve is installed on the outside of the pump body as in the past, and a special seal structure is not required, reducing costs. The present invention provides a pump device that can be made more compact by reducing the number of outwardly projecting parts.

〔Example〕

Hereinafter, the present invention will be explained in detail using embodiments shown in the drawings.

Figures 1 to 5 show an embodiment of a stone pump device according to the present invention, and in these figures, the pump device, which is generally designated by the reference numeral 10, is a pump that sucks in and discharges hydraulic oil. A pump body 12 in which a piston pump 11 etc. is housed, an electric motor 13 attached to one side of the pump body 12 and serving as a driving source for the piston pump 11, and an electric motor 13 attached integrally to the other side of the pump body 12. A space 1S for storing hydraulic oil 14 between the side surface of this body 12
The oil reservoir 15 is made of a thin-walled member having a substantially bottomed cylindrical shape forming a schnitted structure. As shown in FIG. 1, a through space 16 is formed in the center of the upper part of the pump body 12 along the axial direction, and from one end of the through space 16, the motor 1 is opened.
An eccentric camshaft 17 integrally provided on the output shaft taa of No. 3 faces the eccentric camshaft 17, and its eccentric shaft portion 17a is connected to a piston 19, which is a movable portion of the piston pump 11, via a ball bearing 18. In addition, the pump body 12
At the center of the upper end, as shown in Figures 1 and 2,
An oil supply hole 20 is bored into the through space 16 from above, and the other end of the through space 16 is opened toward the inner space 15& of the oil reservoir 15. Therefore, the hydraulic oil 14 supplied from the oil supply hole 20 is transferred to the through space 16 and the internal space 15a of the oil reservoir 15.
This oil supply hole 20 is normally closed by a pleather cap 21 having a plug body 21a made of a sealing material.

As shown in FIG. 1, the motor 13 is joined to one side of the pump body 12 with an O-ring 13b interposed therebetween, and is fixed by a pin 13e. Further, the oil reservoir 15 has an open end Q
The pump body 1 is fitted into the cylindrical part on the other side of the pump body 12 with the IJ ring 15b interposed therein, and is inserted through the bottom of the through hole 15c.
The attachment is fixed on the 2 side, and the insertion end of this through port 15e is sealed with a seal washer 15d.

Also, within the pump body 12, on the same axis as the oil supply hole 20 at the center of the upper end thereof, as shown in FIGS. A series of cylinder holes 22 are formed. By forming the cylinder hole 22 using the oil supply hole 20 in this way, the pleaser cap 21 also serves as a plug for closing the open end of the cylinder hole 22, reducing the number of parts and reducing costs. We are trying to make it possible to achieve reductions, etc.

Here, to briefly explain the general structure of the above-mentioned piston pump 11, reference numeral 23 in the figure is a cylinder body that slidably supports the piston 19, and this cylinder body 23 is inserted into the cylinder hole 22 of the pump body 12. The piston 19 is pressed and held by a spring 24 inserted between the piston 19 and the flange 19 & at the upper end of the piston 19 . A suction valve 25 is integrally incorporated into the lower end of the cylinder body 23, and the suction valve 25 is connected to the pump body 12 with respect to the suction chamber 26 formed at the lower end side of the cylinder hole 22. This is a suction boat that is bored from the side surface on the reservoir 15 side. It is connected to the inside of the reservoir 15 through a suction-side passage hole 27, and a filter-equipped pipe 2B facing inside the reservoir 15 is screwed into this passage hole 27.

Further, a pump chamber 29 formed between the suction valve 25 and the piston 19 in the central portion of the cylinder body 23 is bored from the reservoir 15 side of the pump body 12 and is provided with a blind plug 30a.
It is connected to a passage hole 32 on the discharge side via a discharge valve 31 built into a passage hole 30 that is closed. and,
As shown in FIGS. 2, 4, and 5, the passage hole 32 is guided obliquely upward within the pump body 12, and is directed to the upper right side of the pump body 12 (see FIG. 2).
(first and second discharge bows formed on both sides of the upper end of the ribbon body 12 by a rotary valve body 33b constituting a directional switching valve 33 provided in a pulp hole 3a bored from the outside) 34.35. These two discharge ports 34, 35 and the directional switching valve 33 are used to switch the cylinder in both directions using, for example, a double-acting hydraulic cylinder as a hydraulic actuator for this pump device 10.
When applied to an actuator that only requires pressure oil supply in one direction, only one discharge boat needs to be provided. Furthermore, when the pressure oil from the pump 11 is connected to one boat, the directional control valve 33 connects the other boat to the reservoir 15 through the above-described through space 16 of the body 12.
It is configured to connect to the side. In addition,
2, reference numeral 335 indicates a rond portion 3T where the operation lever (not shown) of the directional control valve 33 that protrudes through the stopper plate 36 attached to the side of the pump device 10 is attached.
.

38 is a passage leading to each of the discharge boats 34 and 35; 34a;
.

Reference numeral 35 & is a filter provided in each discharge boat portion, and as is clear from FIG. Illustrated.

Furthermore, the reference numeral 40 in FIGS. 2 to 4 is a manual piston pump attached as an auxiliary system to the piston pump 11 driven by the motor 13, and is installed inside the pump body 12. A cylinder hole 41 bored from the lower end in parallel with the cylinder hole 22 of the piston pump 11, and a piston 4 that slides inside the cylinder hole 41.
2, and manually for driving this piston 42, (-
43, and a suction valve 45 (see FIG. 3), a discharge valve 46, etc. for sucking and discharging hydraulic oil into the pump chamber 44. Here, the suction system of this manual pump 40 is as follows:
As shown in the second and third figures, the motor-type pump 11
Three passage holes 47a, 47b, 47c leading from the side suction chamber 26 to the suction valve 45, and three passages leading from the suction valve 45 to the pump chamber 44 as shown in FIGS. 3 and 4. Holes 48a, 48b.

480, and the discharge valve 46 is connected to the downstream passage 32 of the discharge passage hole 32 on the motor pump 11 side.
&, and is connected to the directional switching valve 33.

In the pump device 10 having such a configuration, when the motor pump 11 or the manual pump 40 is operated, the hydraulic oil 14 in the oil reservoir 15 is sequentially sucked in and discharged by the pumping action, and further the directional control valve 3
1′ by 3! ! :Take second discharge boat 34.35
The oil is supplied to the actuator side, and the other boat is connected to the oil lisano (15 side) to form a hydraulic circuit, the details of which are easily understood and will not be explained here.

Now, according to the present invention, the pump device 10 as described above
In the pump body 12, a relief nozzle 50 is located in the oil reservoir nozzle 15 of the pump body 12 to recirculate the excess pressure oil to the oil reservoir 15 side when the pressure oil discharged from the pump 11.40 exceeds a set value. It has a distinctive feature in that it is placed on the side.

To explain this in detail, on the oil reservoir 15 side of the pump body 12, on the side facing the internal space 15a,
As shown in FIGS. 1, 2, and 5, a passage hole 51 is formed so as to open into the discharge side passage hole 32 of the motor pump 11. As shown in FIGS. Of course, it is clear that the discharge side passage hole 32 also communicates with the discharge side of the manual pump 40 as described above.

According to this embodiment, as shown in FIG. 1, the balls 52 constituting the relief pulp 50! LN ball holder 52b1 valve seat 52e, and spring 52
A plug body 53 having a plug body 53 incorporated therein is configured to be screwed and attached to the passage hole 51 from the side of the body 12. In the figure, reference numeral 54 indicates a relief pulp set pressure adjustment plug that is screwed into the outer end of the plug body 53, and 55 indicates a nut that fixes the plug body 54 to the plug body 53 at a desired setting position. Reference numeral 56 denotes a spring guide assembled inside the plug body 54, and a relief hole 5T is formed on the side of the plug body 53 to communicate with its internal space.

According to such a configuration, since the relief pulp 50 is located in the oil reservoir 15 even though it is not installed properly, there is no problem even if external oil leaks as in the conventional case. In addition to simplifying the seal structure in this area and reducing costs, we also eliminate the problem of the relief pulp protruding outside the body, which was the case in the past. It can be effective. Further, as in this embodiment, if the relief pulp 50 is incorporated into the plug body 53 and configured separately from the pump body 12, it is not only easy to assemble, but also the relief pulp 50 is Relief pulp with pressure setting work 5
0 can be performed efficiently using a dedicated device alone, and has the advantage that the assembly time of the pump device 10 can be shortened. That is, if a part of the relief pulp 50, such as its valve seat or pulp hole, is provided in the pump body, it is necessary to set the relief pressure after assembling the entire pump, which increases the work time. However, this is not preferable in terms of workability, and the above-mentioned separate structure can solve this problem. but,
Needless to say, the present invention is not necessarily limited to such a separate structure.

Further, the operation of the relief pulp 50 described above is conventionally well known, and the installation work is also well known.
5 to the pump body 12, and the details thereof will be omitted.

It should be noted that the present invention is not limited to the structure of the embodiments described above, and may be modified or changed as appropriate in the type of pump provided in the pump body, its arrangement state, and the shape and structure of each part, including its hydraulic passage. can be used freely, and hydraulic equipment and devices in various fields can be considered as application examples of such a pump device.

〔Effect of the invention〕

As explained above, according to the pump device according to the present invention, the relief pulp that recirculates a part of the discharged oil to the oil reservoir side is attached to the side surface of the pump body located inside the oil reservoir. Despite its simple configuration, there is no need to worry about oil leakage when it is installed on the outer surface of the pump body as in the past, and this eliminates the need for a seal structure, reducing costs and making the entire pump more compact. It has excellent effects, such as being useful for promoting

[Brief explanation of the drawing]

The figures show an embodiment of the pump device according to the present invention, in which Fig. 1 is a longitudinal sectional side view of the whole, Fig. 2 is a sectional view taken along the line ■-■, and Figs. 3 and 4 are 11 in Fig. 2. 5 is a cross-sectional view taken along line v--IV in FIG. 4. 10... Pump device, 11... Motor type piston pump (pump), 12... Pump body, 14
...Hydraulic oil, 15...Oil reservoir, 15&
... Relief internal space, 16 ... Body penetration space, 19 ... Histone (pump movable part), 20.
...Oil supply hole, 22 pa/\ position cylinder hole, 25...
Suction valve, 29...pump chamber, 31...discharge valve,
32...Discharge side passage hole, 33...Directional switching valve,
34.35...Discharge boat, 40...Manual piston pump, 50...Relief valve, 51...
...Passage hole, 52a...Ball, 53...
・Plug body, 5T ・ ・ ・Relief hole. Patent questioner: Automobile Equipment Co., Ltd. agent Masaki Yamakawa (eυ・1 person)

Claims (1)

[Claims] A pump device characterized in that a relief pulp that causes oil discharged from the pump to flow back to an oil reservoir side is provided on a side surface of the pump body located inside the oil reservoir.