CN204610440U - Multistage return filter and pressure test device thereof - Google Patents

Abstract

The utility model discloses a multi-stage oil return filter and a differential pressure detection device thereof. The differential pressure detection device includes a differential pressure transmitter, an oil circuit block and a pipeline, and the number of the differential pressure transmitters is the same as that of the differential pressure transmitter. The stages of the oil return filter are consistent; on each stage of the oil return filter, the differential pressure transmitter is connected to the oil inlet and the oil outlet of the oil return filter element through the oil block and the pipeline. The pipeline is used to detect and compare the pressure of the oil inlet and outlet of the filter element, and send a signal when the pressure difference of the filter element reaches the pressure setting value. Since the multi-stage oil return filter of the utility model is equipped with a pressure difference detection device on each stage of the oil return filter, the pressure difference of each stage of the oil return filter element can be accurately detected. It reminds the operator to replace the filter element in time, and truly realizes multi-stage oil return filtration. Compared with the high-pressure pipeline filter, the operation is easier, the cost is low, and the structure is compact.

Description

Multi-stage oil return filter and its differential pressure detection device

technical field

The utility model relates to an oil return filter and a special device thereof, in particular to a multistage oil return filter and a pressure difference detection device thereof, and belongs to the technical field of pipeline flushing of hydraulic and lubrication systems.

Background technique

The conventional hydraulic system does not need the function of multi-stage oil return filtration, so the oil return filters available on the market do not have the function of really detecting the pressure difference between the upstream and downstream of the filter element; and in pipeline flushing equipment, it is necessary to quickly and efficiently The pollution in the oil is filtered out, and the use of multi-stage filtration has become a trend.

The oil return filter commonly used in the hydraulic system is shown in Figure 1. The oil enters from the A port (oil inlet) of the filter element 3 and flows out from the B port (oil outlet); the oil entering the filter element 3 is restricted by the pores of the filter element. Pressure drop is caused by the flow, and the pressure at port A of the filter element is detected by pressure gauge 1. Since port B of filter element 3 returns directly to the fuel tank and communicates with the atmosphere, it is considered that the pressure detected by pressure gauge 1 is the port A and port B of filter element 3. The difference between the one-way valve 2 and the function of the check valve 2 is that when the pressure difference through the filter element is too large, the oil will be unloaded through the one-way valve 2 to protect the filter element 3 from breakdown due to the excessive pressure difference; but if in When another oil return filter is connected in series behind port B of the filter element 3 instead of being directly connected to the oil tank, the pressure detected by the pressure gauge 1 at this time is not the pressure difference through the filter element 3.

It can be seen from the above description that since the oil outlet of the oil return filter is designed to return directly to the oil tank and communicate with the atmosphere, and the pressure gauge attached to the oil return filter is set upstream of the oil return filter element, when the oil return filter When the filter is working, it will detect the upstream pressure of the filter element, and the downstream pressure will default to the atmospheric pressure value, so directly use the oil inlet pressure value as the pressure difference between the upstream and downstream. If the oil outlet of the oil return filter is connected to the second stage oil return filter When the pressure gauge or other additional equipment is not directly connected to the atmosphere, the so-called differential pressure value detected by the pressure gauge will be wrong, which is not conducive to setting up a multi-stage oil return filter.

Utility model content

The purpose of this utility model is to solve the above-mentioned defects of the prior art and provide a pressure difference detection device for a multi-stage oil return filter. The pressure difference detection device has a simple structure and can detect the The real pressure difference in the downstream will remind the operator to replace the filter element in time when the pressure difference is too large.

Another object of the present utility model is to provide a multi-stage oil return filter including the above-mentioned differential pressure detection device.

The purpose of this utility model can be achieved by taking the following technical solutions:

The pressure difference detection device of the multi-stage oil return filter includes a pressure difference transmitter, an oil block and a pipeline, and the number of the pressure difference transmitter is consistent with the number of stages of the oil return filter; at each stage On the oil return filter, the differential pressure transmitter is connected to the oil inlet and oil outlet pipeline of the oil return filter element through the oil block and the pipeline, and is used to detect the oil inlet and the oil outlet of the filter element The pressure is compared and a signal is sent when the pressure difference of the filter element reaches the pressure setting value.

Another purpose of the utility model can be achieved by taking the following technical solutions:

Multi-stage oil return filter, including the above-mentioned pressure difference detection device, the oil outlet of the former stage oil return filter element is connected with the oil inlet port of the latter stage oil return filter element; the oil is returned from the first stage The oil inlet of the filter element enters, and after multi-stage filtration, returns to the fuel tank through the oil outlet of the last stage oil return filter element.

Preferably, a one-way valve is provided on each stage of the oil return filter, and the one-way valve is used to control oil unloading when the pressure difference of the filter element of the oil return filter reaches a pressure setting value.

Preferably, the one-way valve is connected to the pipelines of the oil inlet and the oil outlet of the oil return filter element through pipelines.

Compared with the prior art, the utility model has the following beneficial effects:

1. The pressure difference detection device of the present utility model adopts a pressure difference transmitter to connect to the upstream and downstream of the filter element of the oil return filter through the oil circuit block and the pipeline (the pipeline of the oil inlet of the filter element is the upstream of the filter element, and the pipeline of the oil outlet of the filter element The pipeline is downstream of the filter element), compared with the traditional oil return filter using a pressure gauge for detection, it can detect the real pressure difference between the upstream and downstream of the filter element to avoid false signals.

2. The multi-stage oil return filter of the utility model can be arranged on the oil tank panel. Since a pressure difference detection device is installed on each stage of the oil return filter, the pressure difference of each stage of the oil return filter element can be detected. It detects accurately and reminds the operator to replace the filter element in time when the pressure difference is too large, and truly realizes multi-stage oil return filtration. Compared with the high-pressure pipeline filter, the operation is easier, the cost is low, and the structure is compact.

Description of drawings

Fig. 1 is a schematic structural diagram of a traditional oil return filter.

Fig. 2 is a structural schematic diagram of a two-stage oil return filter using a differential pressure detection device of the present invention.

In Fig. 1, 1-pressure gauge, 2-check valve, 3-filter element.

In Figure 2, 1-first stage oil return filter, 2-second stage oil return filter, 3-first filter element, 4-first one-way valve, 5-second filter element, 6-second one-way Valve, 7-first differential pressure transmitter, 8-second differential pressure transmitter.

Detailed ways

The utility model will be further described in detail below in conjunction with the embodiments and accompanying drawings, but the implementation of the utility model is not limited thereto.

Example 1:

As shown in Figure 2, this embodiment takes a two-stage oil return filter as an example, and the two-stage oil return filters are respectively a first-stage oil return filter 1 and a second-stage oil return filter 2; The primary oil return filter 1 includes a first filter element 3 and a first one-way valve 4, and the first one-way valve 4 is connected to the A1 port (oil inlet) and the B1 port (outlet port) of the first filter element 3 through pipelines. oil port); the second stage oil return filter 2 includes a second filter element 5 and a second one-way valve 6, and the second one-way valve 6 is connected to the A2 port of the second filter element 5 through a pipeline (oil inlet) and B2 port (oil outlet); the B1 port of the first filter element 3 is connected with the A2 port of the second filter element 5; the oil enters from the A1 port of the first filter element 3, and passes through After the two-stage filtration, it returns to the oil tank through the B2 port of the second filter element 5.

The differential pressure detection device of this embodiment includes two differential pressure transmitters (the model is CMS, and the brand is LEEMIN), an oil block and pipelines. The two differential pressure transmitters are the first differential pressure transmitters respectively. Signal device 7 and second differential pressure signal device 8;

On the first-stage oil return filter 1, the first differential pressure transmitter 7 is connected to the pipelines of the A1 port and the B1 port of the first filter element 3 through the oil block and the pipeline; The A1 port of the filter element 3 enters and flows out from the B1 port. The oil entering the first filter element 3 is throttled by the pores of the filter element to cause a pressure drop. 7 Simultaneous detection and comparison, when the pressure difference reaches the pressure setting value of the first differential pressure transmitter 7, it means that the pressure difference is too large, and the first differential pressure transmitter 7 sends out visual and electrical signals to remind the operation Personnel replace the first filter element 3 in time; since the first stage oil return filter 1 also has the first one-way valve 4, if the operator does not replace the first filter element 3 in time, the pressure difference will further increase. When the opening pressure of the valve 4 is set, the first one-way valve 4 is opened, and the oil will be unloaded through the first one-way valve 4, so as to protect the first filter element 3 from breakdown due to excessive pressure difference;

Similarly, on the second-stage oil return filter 2, the second differential pressure transmitter 8 is connected to the pipelines of the A2 port and the B2 port of the second filter element 5 through the oil block and the pipeline, when the oil It flows out from the B1 port of the first filter element 3, then enters from the A2 port of the second filter element 5, and flows out from the B2 port. The pressures at port B2 and port B2 are simultaneously detected and compared by the second differential pressure transmitter 8. When the differential pressure reaches the pressure setting value of the second differential pressure transmitter 8, it means that the differential pressure is too large, and the second differential pressure The differential transmitter 8 sends visual and electrical signals to remind the operator to replace the second filter element 5 in time; since the second stage oil return filter 2 also has a second one-way valve 6, if the operator does not replace the second filter element in time 5. The pressure difference will further increase. When the opening pressure setting value of the second one-way valve 6 is reached, the second one-way valve 6 will open, and the oil will be unloaded through the second one-way valve 6 to protect the second filter element 5 will not be broken down by excessive pressure difference.

In summary, since the multi-stage oil return filter of the present invention is equipped with a pressure difference detection device on each stage of the oil return filter, the pressure difference of each stage of the oil return filter element can be accurately detected, When the pressure difference is too large, the operator is reminded to replace the filter element in time, and the multi-stage oil return filter is truly realized. Compared with the high-pressure pipeline filter, the operation is easier, the cost is low, and the structure is compact.

The above is only a preferred embodiment of the utility model, but the scope of protection of the utility model is not limited thereto. For example, the oil return filter used can also be a three-stage or above oil return filter. Within the scope disclosed by the utility model, those skilled in the art may make equivalent replacements or changes according to the technical solution of the utility model and the concept of the utility model, which all belong to the protection scope of the utility model.

Claims (4)

1. the pressure test device of multistage return filter, is characterized in that: comprise differential pressure transmitter device, manifold block and pipeline, and the quantity of described differential pressure transmitter device is consistent with the progression of return filter; On every one-level return filter, described differential pressure transmitter device is connected to the filler opening of return filter filter core and the pipeline of oil outlet by manifold block and pipeline, for the pressure of the filler opening and oil outlet that detect return filter filter core, and compare, send signal when the pressure reduction of return filter filter core reaches pressure set points.

2. multistage return filter, is characterized in that: comprise pressure test device according to claim 1, and the oil outlet of previous stage return filter filter core is connected with the filler opening of rear stage return filter filter core; Fluid enters from the filler opening of first order return filter filter core, after multistage filtering, get back to fuel tank by the oil outlet of afterbody return filter filter core.

3. multistage return filter according to claim 2, is characterized in that: on every one-level return filter, be provided with one-way valve, and described one-way valve is used for when the pressure reduction of return filter filter core reaches the off-load of pressure set points time control liquefaction liquid.

4. multistage return filter according to claim 3, is characterized in that: described one-way valve is connected to the filler opening of return filter filter core and the pipeline of oil outlet by pipeline.