Air tightness detection device for hydraulic clutch of forklift

Abstract

The utility model discloses a forklift hydraulic clutch air tightness detection device, which comprises a controller and a closed container, and is characterized in that the closed container is provided with a second connecting seat, and the second connecting seat is provided with a first connector and a second connector; the first connector and the second connector are respectively communicated with a first oil inlet communicated with the first working cavity and a second oil inlet communicated with the second working cavity on the hydraulic clutch in the closed container as well as a detection pipeline corresponding to the working cavity outside the closed container, and the detection pipeline is connected with an air source; and the controller is respectively in signal connection with the detection pipeline and the execution element and the detection element on the closed container. The hydraulic clutch is sealed in the closed container, the temperature in the closed container is slightly influenced by the environment, so that the temperature of an oil product in the working cavity is kept stable, the accuracy of leakage rate measurement is improved, compressed air is adopted to replace the oil product for a predelivery test of the hydraulic clutch, the test cost is reduced, and the test efficiency is improved. And pollution and consumption are reduced, and maintenance is easy.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of engineering machinery, and more particularly, to a gas tightness detection device for a forklift hydraulic clutch. BACKGROUND

[0002] The hydraulic clutch, as a main part in the hydraulic transmission box of a forklift, is directly related to the performance of the transmission system of the whole vehicle and is an important part for ensuring the reliable operation of the whole vehicle.

[0003] The current factory test of the forklift hydraulic clutch is carried out by using a hydraulic pump station. In a static state, constant pressure and constant flow pressure oil is supplied to the working cavity of the hydraulic clutch, and the pressure established by the forward gear and the reverse gear of the clutch under the constant flow and constant pressure is detected to determine whether the sealing performance of the clutch meets the requirements.

[0004] The hydraulic pump test method has the following problems:

[0005] 1) High test cost: The hydraulic oil is subject to oil pollution, and the test oil needs to be replaced, supplemented and purified regularly, which increases the cost of oil procurement and the cost of oil purification machine consumables and causes energy waste;

[0006] 2) Easy to cause pollution: The residual oil in the clutch after completing the test cannot be completely drained, which easily causes oil pollution on the transmission assembly line;

[0007] 3) The oil pressure test bench occupies a large area, affects the overall process layout of the workshop, and is difficult to maintain and repair.

[0008] 4) The clutch is exposed in an open space, and the oil is easily affected by the environment temperature, so the oil pressure in the working cavity is affected by the environment temperature, thereby causing inaccurate measurement of the leakage amount. CONTENT OF THE INVENTION

[0009] The present application provides a gas tightness detection device for a forklift hydraulic clutch, which seals the hydraulic clutch in a sealed container. The temperature in the sealed container is less affected by the environment, so the oil temperature in the working cavity remains stable, thereby improving the accuracy of the leakage measurement. In addition, the present application uses compressed air instead of oil to carry out the factory test of the hydraulic clutch, which reduces the test cost, reduces pollution and consumption, and is easy to maintain and repair.

[0010] The application provides a kind of forklift hydraulic clutch airtightness detection device, including controller and closed container, second connecting seat is equipped on closed container, first connecting head and second connecting head are equipped on second connecting seat, first connecting head and second connecting head are respectively communicated with the first oil inlet of first working cavity and the second oil inlet of second working cavity on the hydraulic clutch in closed container and the detection pipeline of corresponding working cavity outside closed container is communicated, detection pipeline is connected with gas source;

[0011] Controller is connected with detection pipeline and the signal of execution element and detection element on closed container.

[0012] Preferably, first connecting head and gas source and second connecting head and gas source are respectively provided with impact pipeline for first working cavity and impact pipeline for second working cavity;

[0013] Controller is connected with the signal of execution element on impact pipeline.

[0014] Preferably, impact pipeline is provided with one-way valve and pneumatic impact valve, and controller is connected with the signal of pneumatic impact valve.

[0015] Preferably, detection pipeline includes detection main pipe shared by two working cavities and detection branch pipe arranged between detection main pipe and corresponding working cavity.

[0016] The other end of detection main pipe is connected with gas source, and gas flow adjusting and detecting device, first pressure gauge and first pressure transmitter are arranged on detection main pipe, and electromagnetic valve is arranged on detection branch pipe.

[0017] Controller is connected with the signal of first pressure transmitter, execution element of gas flow adjusting and detecting device and electromagnetic valve.

[0018] Preferably, gas flow adjusting and detecting device includes one or more of filter, restrictor, pressure regulating valve, gas source three-in-one, flowmeter.

[0019] Preferably, second pressure gauge and second pressure transmitter are arranged on closed container, and second pressure transmitter is connected with the signal of controller.

[0020] Preferably, weighing sensor is arranged below closed container, and weighing sensor is connected with the signal of controller.

[0021] Preferably, end of detection main pipe is provided with three-position five-way reversing valve, first position and second position of three-position five-way reversing valve are connected with the end of two detection branch pipes respectively, and the other end of two detection branch pipes is connected with first connecting head and second connecting head respectively; when three-position five-way reversing valve is in third position, two detection branch pipes are not conducted.

[0022] Other features and advantages of the application will become apparent from the following detailed description of exemplary embodiments thereof, with reference to the drawings. Attached Figure Description

[0023] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments of the present application and, together with their description, serve to explain the principles of the present application.

[0024] Figure 1 A schematic diagram of the airtightness testing device for the forklift hydraulic clutch provided in this application;

[0025] Figure 2 A schematic diagram of the airtightness testing device used in the production site provided in this application;

[0026] Figure 3 for Figure 2 Structural diagram of the first connecting seat;

[0027] Figure 4 A schematic diagram of the structural principle of one embodiment of the airtightness testing device for laboratory use provided in this application;

[0028] Figure 5 A schematic diagram of the structural principle of one embodiment of the airtightness testing device for laboratory use provided in this application. Detailed Implementation

[0029] Various exemplary embodiments of the present application will now be described in detail with reference to the accompanying drawings. It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the present application.

[0030] The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the scope of this application and its application or use.

[0031] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, they should be considered part of the specification.

[0032] In all the examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.

[0033] This application provides an airtightness testing device for a forklift hydraulic clutch. The hydraulic clutch is sealed in a closed container, and the temperature inside the closed container is less affected by the environment. Therefore, the oil temperature in the working chamber remains stable, thereby improving the accuracy of leakage measurement. Furthermore, this application uses compressed air instead of oil for the factory test of the hydraulic clutch, which reduces testing costs, pollution and consumption, and makes maintenance easier.

[0034] likeFigure 1 As shown, the hydraulic clutch 50 under test has a first working chamber 501 corresponding to the forward gear piston of the forklift and a second working chamber 502 corresponding to the reverse gear piston of the forklift. The ends of the forward gear piston and the reverse gear piston are both equipped with sealing rings, which play a key role in the sealing of the working chambers.

[0035] like Figure 1 As shown, the air tightness testing device for the forklift hydraulic clutch provided in this application includes a controller (not shown in the figure) and a testing pipeline connected to each working chamber of the hydraulic clutch 50.

[0036] The detection pipeline includes a main detection pipe shared by the two working chambers and detection branch pipes located between the main detection pipe and the corresponding working chamber. The other end of the main detection pipe is connected to an air source, and the main detection pipe is equipped with an airflow regulating and detection device, a first pressure gauge, and a first pressure transmitter. A solenoid valve is installed on the detection branch pipe.

[0037] The controller is connected to the actuators and sensors on the detection pipeline. In other words, the controller is connected to the actuators and solenoid valves in the first pressure transmitter, the airflow regulating and detection device. The first pressure transmitter is used to convert the gas pressure in the detection pipeline into a pneumatic or electric signal and transmit it to the controller. The controller controls the actuators and solenoid valves in the airflow regulating and detection device to perform actions based on the pressure signal.

[0038] The airflow regulation and detection device includes one or more of the following: filter, throttle, pressure regulating valve, air source triplet, and flow meter. Figure 1 In the embodiment shown, the airflow regulation and detection device on the detection manifold includes a filter 15, a precision pressure regulating valve 16, and a flow meter 18. A first pressure gauge 17 is disposed between the precision pressure regulating valve 16 and the flow meter 18, and a first pressure transmitter 19 is disposed downstream of the flow meter 18.

[0039] exist Figure 1 In the embodiment shown, a first two-way solenoid valve 14 is provided on the detection branch corresponding to the first working chamber 501, and a second two-way solenoid valve 13 is provided on the detection branch corresponding to the second working chamber 502.

[0040] Preferably, the airtightness testing device further includes an impact pipeline, the other end of which is connected to the air source 60, and the actuator on the impact pipeline is signal-connected to the controller. As one embodiment, the impact pipeline is equipped with a one-way valve and a pneumatic impact valve, and the controller is signal-connected to the pneumatic impact valve. The controller controls the pneumatic impact valve to operate based on the pressure signal in the impact pipeline.

[0041] Figure 1In the shown embodiment, for the first working chamber 501, its corresponding impact pipeline includes the first pneumatic impact valve 12 and the one-way valve between the air source 60 and the air inlet of the first working chamber 501. For the second working chamber 502, its corresponding impact pipeline includes the second pneumatic impact valve 11 and the one-way valve between the air source 60 and the air inlet of the second working chamber 502.

[0042] Based on the above preferred embodiment, the air tightness detection method of the hydraulic clutch executed by the controller includes:

[0043] P1: control one of the pneumatic impact valves (e.g. 12) to be powered on at a high frequency, so that the impact pipeline is turned on, and the compressed air enters the corresponding working chamber (e.g. the first working chamber 501) of the hydraulic clutch being detected through the pneumatic impact valve and the one-way valve, thereby pushing the piston (e.g. the forward gear piston) to move towards the other working chamber.

[0044] P2: control the pneumatic impact valve to be powered on and powered off according to a preset time interval and a preset number of vibrations, and control the pneumatic impact valve to be powered off after reaching the preset number of vibrations.

[0045] Specifically, the pneumatic impact valve is powered on for a first preset time (e.g. 100-1000 ms) and then powered off for a second preset time. Due to the existence of leakage, the gas pressure in the working chamber decreases, and the piston returns under the action of the return spring, thereby the piston realizes one reciprocation. By controlling the controller to cycle the pneumatic impact valve to be powered on and powered off at a high frequency, the piston moves back and forth at a high frequency to generate vibration, so that the sealing ring on the piston is more tightly attached to the piston rod, thereby improving the sealing performance and reducing the leakage.

[0046] P3: after completing the high-frequency vibration, control the corresponding electromagnetic valve (e.g. the first two-way electromagnetic valve 14) of the working chamber (e.g. the first working chamber) to be powered on, and control the detection pipeline to be turned on, so that the compressed air flows into the flow restrictor, and then enters the corresponding working chamber of the hydraulic clutch being detected through the electromagnetic valve after the throttling action of the flow restrictor, thereby increasing the pressure in the working chamber.

[0047] P4: after the pressure in the working chamber reaches a preset value, control the electromagnetic valve to be powered off, and the working chamber enters a pressure maintaining state. During the pressure maintaining process, the pressure in the working chamber decreases due to the existence of leakage.

[0048] P5: after a preset pressure maintaining time, calculate the leakage of the working chamber, and obtain the air tightness detection result of the working chamber according to the leakage, thereby completing the air tightness detection of one of the working chambers. If the leakage is less than a threshold value, the sealing performance is qualified; otherwise, the sealing performance is unqualified.

[0049] Preferably, the controller is a PLC controller. After the PLC controller completes the airtightness test in one of the working chambers, it automatically controls the airtightness testing device to perform airtightness testing in the other working chamber according to the above steps, thereby realizing fully automatic airtightness testing.

[0050] As an example, the aforementioned airtightness testing device is installed at the production site, and its structure is as follows: Figure 2 As shown, based on the above, the airtightness testing device also includes a sliding frame 21 mounted above the clutch production line, a first connecting seat 23 suspended below the sliding frame 21, and a testing chamber (not shown in the figure) separately from the first connecting seat 23. A balancer 22 is provided on the rope between the sliding frame 21 and the first connecting seat 23. The sliding frame 21 includes a transverse slide rail and a longitudinal slide rail. The first connecting seat 23 can slide in both the longitudinal and transverse directions to move it directly above the hydraulic clutch output from the production line for convenient testing. The testing chamber contains a pipe connected to the air source 60, a portion of the testing pipeline, and a portion of the impact pipeline. A one-way valve, airflow regulator, testing device, and solenoid valve are located within the testing chamber.

[0051] The first connecting seat is provided with a first air inlet communicating with the first working chamber and a second air inlet communicating with the second working chamber. The first air inlet and the second air inlet are respectively connected to the impact pipeline and the detection pipeline of the corresponding working chamber.

[0052] As an example, such as Figure 3 As shown, the lower part of the first connecting seat 23 is provided with a slot 239 for connecting to the end of the hydraulic clutch, and the two opposite side walls of the slot are respectively provided with a first air inlet 233 and a second air inlet 234.

[0053] The first connecting seat 23 and the detection chamber are respectively provided with a portion of the detection pipeline for the first working chamber and the second working chamber. The detection pipelines on the first connecting seat 23 for the first working chamber and the second working chamber are respectively connected to the first air inlet and the second air inlet. Specifically, a horizontal first pipe 236 is provided between the first air inlet 233 and the left side wall of the first connecting seat 23, and a first connection port 237 is formed at the end of the first pipe 236. The first connection port 237 is connected to the corresponding first two-way solenoid valve 14 in the detection chamber through a connector and a gas pipe to form a detection pipeline for the first working chamber.

[0054] A part of the impact pipeline for the first working chamber and the second working chamber is respectively arranged on the first connecting seat 23 and in the detection box. The impact pipeline in the detection box is connected with the compressed air source outside the detection box. Specifically, the left end of the upper side wall of the first connecting seat 23 is provided with a vertical second pipeline 235. The middle part of the second pipeline 235 is in communication with the middle part of the first pipeline 236. The upper end of the second pipeline 235 is provided with a second connecting port 231. The second connecting port 231 is connected with the first pneumatic impact valve 12, so that the second pipeline 235 and the first pipeline 236 constitute a part of the impact pipeline for the first working chamber. The first pneumatic impact valve 12 is connected with the air source 60 through the pipeline outside the detection box and the impact pipeline in the detection box in sequence.

[0055] The right end of the upper side wall of the first connecting seat 23 is symmetrically provided with the impact pipeline and the detection pipeline connected with the second working chamber.

[0056] In the working state, one end of the oil inlet (including the first oil inlet connected with the first working chamber and the second oil inlet connected with the second working chamber, the oil inlet is used for air inlet in the present application) of the detected hydrodynamic clutch is inserted into the insertion slot of the first connecting seat, so that the first air inlet is aligned with the first oil inlet of the hydrodynamic clutch, and the second air inlet is aligned with the second oil inlet of the hydrodynamic clutch. The first air inlet is in communication with the first working chamber of the detected hydrodynamic clutch, and the second air inlet is in communication with the second working chamber of the detected hydrodynamic clutch, so that the impact pipeline and the detection pipeline of the first working chamber are in communication with the first working chamber of the detected hydrodynamic clutch, and the impact pipeline and the detection pipeline of the second working chamber are in communication with the second working chamber of the detected hydrodynamic clutch.

[0057] In this embodiment, when calculating the leakage amount, the leakage amount is calculated according to the change value of the first pressure gauge 17 at the end of the pressure maintaining. As an example, the ratio of the pressure change value to the pressure value at the beginning of the pressure maintaining is taken as the leakage amount.

[0058] As another example, the air tightness detection device of the forklift hydrodynamic clutch is installed in a laboratory. The air tightness detection device further comprises a closed container with a constant volume. The closed container is provided with a second connecting seat. The second connecting seat is provided with a first connecting head for the first working chamber and a second connecting head for the second working chamber. The first connecting head and the second connecting head are respectively in communication with the first oil inlet connected with the first working chamber and the second oil inlet connected with the second working chamber of the hydrodynamic clutch and the detection pipeline of the corresponding working chamber outside the closed container. During detection, the hydrodynamic clutch is closed in the closed container. The temperature in the closed container is less affected by the environment, so the temperature of the oil in the working chamber remains stable, thereby improving the accuracy of the leakage amount measurement.

[0059] As an example, on the basis of the above, Figure 4An embodiment in a laboratory is shown. As shown in Figure 4 The closed container 31 is provided with a second pressure gauge 33 and a second pressure transmitter 32, and the second pressure transmitter 32 is connected to the controller. The gas flow adjustment and detection device on the detection manifold includes a gas source triple 34, a precision pressure regulating valve 35, and a fixed restrictor 38. A third pressure gauge 36 and a third pressure transmitter 37 are arranged between the precision pressure regulating valve 35 and the fixed restrictor 38.

[0060] In this embodiment, the electromagnetic valve is a three-position five-way directional valve. Specifically, the end of the detection manifold is provided with a three-position five-way directional valve, the first and second positions of which are connected to the ends of two detection branch pipes, and the other ends of the two detection branch pipes are connected to a first connection head and a second connection head, respectively. When the three-position five-way directional valve is in the third position, neither of the two detection branch pipes is open. In this embodiment, when detection is performed using the detection pipeline, the controller controls the three-position five-way directional valve to open the detection pipeline of the target working chamber, and injects compressed air into the target working chamber (see the above description regarding Figure 1 When the pressure of the gas in the working chamber reaches the preset value, pressure maintenance detection is started. Due to the leakage of the clutch, the gas in the hydraulic clutch leaks into the closed container during the pressure maintenance process, so that the pressure value in the closed container gradually increases, and the value of the second pressure gauge 33 changes. When calculating the leakage amount, the leakage amount is calculated based on the change value of the second pressure gauge 33 at the end of the pressure maintenance.

[0061] Preferably, based on the embodiment shown in Figure 4 The first connection head and the second connection head are respectively provided with an impact pipeline for the first working chamber and an impact pipeline for the second working chamber, and the impact pipelines are respectively provided with a one-way valve and a pneumatic impact valve. The impact vibration principle is described above regarding Figure 1 .

[0062] As another embodiment, the air tightness detection device in the laboratory is shown in Figure 5As shown, a second pressure gauge 42 and a second pressure transmitter 43 are provided on the sealed container 41, and the second pressure transmitter 43 is connected to the controller signal. The airflow regulation and detection device on the detection main pipe includes an air source triplet 45, a precision pressure regulating valve 46, and a fixed throttle 49. A fourth pressure gauge 47 and a fourth pressure transmitter 48 are positioned between the precision pressure regulating valve 46 and the fixed throttle 49. A three-position five-way directional valve is provided at the end of the detection main pipe. Its first and second positions are respectively connected to the ends of two detection branch pipes, and the other ends of the two detection branch pipes are respectively connected to a first connector and a second connector. When the three-position five-way directional valve is in the third position, neither detection branch pipe is conductive. Furthermore, a weighing sensor 44 is provided below the sealed container 41, and the weighing sensor 44 is connected to the controller signal. In this embodiment, when using the detection pipeline for detection, the controller controls the three-position five-way directional valve to open the detection pipeline of the target working chamber, injecting compressed air into the target working chamber (see above regarding...). Figure 1 (As explained), after the gas pressure in the working chamber reaches the preset value, pressure holding detection begins. Due to clutch leakage, during the pressure holding process, gas leaks from the hydraulic clutch into the sealed container, causing the pressure value in the sealed container to gradually increase, the total mass of air in the sealed container to gradually increase, and the mass value detected by the weighing sensor 44 to gradually increase. When calculating the leakage amount, the leakage amount is calculated based on the change value of the weighing sensor 44 at the end of the pressure holding period. Using the weighing sensor can more accurately detect the change caused by leakage, improving the accuracy of leakage measurement.

[0063] Preferably, in Figure 5 Based on the illustrated embodiment, an impact pipeline for the first working chamber and an impact pipeline for the second working chamber are respectively provided between the first connector and the air source 60 and between the second connector and the air source 60. These impact pipelines are equipped with a one-way valve and a pneumatic impact valve. The impact vibration principle is explained in the above description. Figure 1 Explanation.

[0064] The beneficial effects of this application are as follows:

[0065] 1. The instrument consumes less than 100 watts, with no electrical energy consumption; compressed air consumption is approximately 100L per unit, which is negligible. There is no oil consumption during the test, eliminating the need for regular oil replacement, replenishment, and purification. This reduces the cost of test oil and oil purification consumables, enabling clean production for hydraulic clutch factory testing. Furthermore, it eliminates the oil draining process required for oil testing, avoiding site and production line contamination caused by oil testing, and also reduces the workload of instrument maintenance.

[0066] 2. Good appearance: The air tightness detection device arranged in the production site is arranged at the edge of the production line. The detection box has small volume and occupies an area of about 0.5 square meters. The connecting seat is installed in a suspension mode, without occupying an area, and the image of the production line operation in the workshop is improved.

[0067] 3. Low labor intensity: In the example in the production site, when the finished clutch flows to the detection station, the operator pulls down the test tool to cover the tested clutch, and presses the test button to complete the test. The clutch does not need to be carried to the detection site outside the production line, which greatly reduces the labor intensity.

[0068] Although some specific embodiments of the present application have been described in detail through examples, those skilled in the art should understand that the above examples are only for illustration, not for limiting the scope of the present application. Those skilled in the art should understand that the above embodiments can be modified without departing from the scope and spirit of the present application. The scope of the present application is defined by the appended claims.

Claims

1. A device for detecting air tightness of a hydraulic clutch of a fork lift truck, characterized by, The application relates to a hydraulic clutch control system, which comprises a controller and a closed container, wherein a second connecting seat is arranged on the closed container, a first connecting head and a second connecting head are arranged on the second connecting seat, the first connecting head and the second connecting head are respectively connected with a first oil inlet and a second oil inlet of a hydraulic clutch in the closed container, and a detection pipeline of a corresponding working cavity outside the closed container is connected with a gas source. The controller is respectively connected with the detection pipeline, an executing element and a detecting element on the closed container.

2. The air tightness testing device for a forklift hydraulic clutch according to claim 1, wherein The first connecting head and the second connecting head are respectively connected with an impact pipeline for a first working cavity and an impact pipeline for a second working cavity. The controller is connected with an executing element on the impact pipeline.

3. The air tightness testing device for a forklift hydraulic clutch according to claim 2, wherein A one-way valve and a pneumatic impact valve are arranged on the impact pipeline, and the controller is connected with the pneumatic impact valve.

4. The air tightness testing device for a forklift hydraulic clutch according to claim 1, wherein The detection pipeline comprises a detection main pipeline shared by two working cavities and a detection branch pipeline arranged between the detection main pipeline and a corresponding working cavity. The other end of the detection main pipeline is connected with the gas source, a gas flow adjusting and detecting device, a first pressure gauge and a first pressure transmitter are arranged on the detection main pipeline, and an electromagnetic valve is arranged on the detection branch pipeline. The controller is connected with the first pressure transmitter, an executing element of the gas flow adjusting and detecting device and the electromagnetic valve.

5. The air tightness testing device for a forklift hydraulic clutch according to claim 4, wherein The gas flow adjusting and detecting device comprises one or more of a filter, a throttle, a pressure regulating valve, a gas source three-way joint and a flowmeter.

6. The air tightness testing device for a forklift hydraulic clutch according to claim 1, wherein A second pressure gauge and a second pressure transmitter are arranged on the closed container, and the second pressure transmitter is connected with the controller.

7. The device for detecting air tightness of a forklift hydraulic clutch according to claim 6, wherein A weighing sensor is arranged below the closed container, and the weighing sensor is connected with the controller.

8. The air tightness testing device for a forklift hydraulic clutch according to claim 4, wherein An end of the detection main pipeline is provided with a three-position five-way reversing valve, the first position and the second position of the three-position five-way reversing valve are respectively connected with the ends of two detection branch pipelines, the other ends of the two detection branch pipelines are respectively connected with the first connecting head and the second connecting head, and when the three-position five-way reversing valve is in the third position, the two detection branch pipelines are not connected.

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