An electromagnetic force direct test device for an automotive air conditioning electromagnetic clutch

Abstract

The present invention discloses a direct electromagnetic force testing device for an automotive air-conditioning electromagnetic clutch, which can directly test the electromagnetic force of the electromagnetic clutch. The direct electromagnetic force testing device includes: a base, a mounting seat, and a fixed shaft, which are made of non-magnetic materials and are cylindrical in shape. The fixed shaft is slidably fitted in the inner hole of the mounting seat. The lower end of the fixed shaft is used to mount the armature of the electromagnetic clutch. An annular mounting space is provided on the outer peripheral surface of the lower part of the mounting seat for mounting the pulley and the electromagnetic coil of the electromagnetic clutch. The base is used to position the lower end of the pulley of the electromagnetic clutch, and the inner hole of the base is used to make way for the armature and the fixed shaft.

Description

Technical Field

[0001] The present invention relates to the technical field of electromagnetic clutches, and particularly to a direct electromagnetic force testing device for an electromagnetic clutch of an automotive air conditioner. Background Art

[0002] An electromagnetic clutch of an automotive air conditioner generally consists of three parts: a driving wheel assembly, an armature assembly, and an electromagnetic coil assembly (as shown in Figure 1 ). When the coil is energized, magnetic force is generated, and the armature suction cup overcomes the deformation resistance of the reed and engages with the pulley suction cup, thereby realizing the operation and stop of the compressor. Currently, there is no device for directly testing the electromagnetic force of an electromagnetic clutch. Summary of the Invention

[0003] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a direct electromagnetic force testing device for an electromagnetic clutch of an automotive air conditioner, which can directly test the electromagnetic force of the electromagnetic clutch.

[0004] The purpose of the present invention is achieved as follows:

[0005] A direct electromagnetic force testing device for an electromagnetic clutch of an automotive air conditioner includes: a base, a mounting seat, and a fixed shaft. The base, the mounting seat, and the fixed shaft are all made of non-magnetic materials. The base and the mounting seat are both cylindrical. The fixed shaft is slidably fitted in the inner hole of the mounting seat. An installation head is provided at the lower end of the fixed shaft, and the installation head is used to install the armature of the electromagnetic clutch. An annular installation space is provided on the outer peripheral surface of the lower part of the mounting seat for installing the pulley and the electromagnetic coil of the electromagnetic clutch. The base is located directly below the mounting seat, and the inner diameter of the base is larger than the outer diameter of the mounting seat. The base is used to position the lower end of the pulley of the electromagnetic clutch, and the inner hole of the base is used to make way for the armature and the fixed shaft.

[0006] Preferably, when the fixed shaft is in the lower limit position, the upper end of the fixed shaft extends out of the inner hole of the mounting seat.

[0007] Preferably, the fixed shaft is slidably fitted in the inner hole of the mounting seat through a cage.

[0008] Preferably, a nut is threadedly fitted at the lower end of the annular installation space for axially locking the pulley.

[0009] Preferably, a snap ring is sleeved on the upper part of the annular installation space. The snap ring is provided with a positioning protrusion along the axial direction. A positioning hole is provided on the mounting seat to cooperate with the positioning protrusion to form circumferential positioning of the snap ring. The snap ring is used to cooperate with the nut to clamp the pulley and the electromagnetic coil.

[0010] Preferably, an annular clamping groove is provided at the upper end of the base for axially positioning and radially positioning the pulley.

[0011] Preferably, the pulley, the electromagnetic coil, and the armature are installed on the electromagnetic force direct test device; the electromagnetic force direct test device is installed on the press.

[0012] Working method: The electromagnetic coil is energized to make the pulley and the armature attract each other.

[0013] The press presses downward on the fixed shaft until the pulley and the armature are separated, and the press pressure is obtained.

[0014] Calculation: Gravity of the fixed shaft + Press pressure = Electromagnetic force of the electromagnetic clutch.

[0015] Preferably, the lower end suction surface air gap of the pulley is filled with non-magnetic conductive material to increase the stiffness of the pulley suction surface.

[0016] Preferably, the pulley is installed on the mounting seat through bearings.

[0017] Due to the adoption of the above technical solutions, the present invention has the following beneficial effects:

[0018] The present invention can directly test the electromagnetic force of the electromagnetic clutch. Through two sets of experimental verifications and electromagnetic force theoretical analysis, the accuracy rate of the test results is more than 90%. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a structural schematic diagram of the present invention;

[0020] Figure 2 is a schematic diagram of the CAE analysis of the pulley;

[0021] Figure 3 is a schematic diagram of the relationship between the deformation displacement of the pulley and the suction force;

[0022] Figure 4 is a schematic diagram of the influence of the displacement deformation of the pulley on the test.

[0023] REFERENCE SIGNS

[0024] In the drawings, 1 is the base, 2 is the mounting seat, 3 is the fixed shaft, 4 is the cage, 5 is the nut, 6 is the snap ring, 7 is the pulley, 8 is the armature, and 9 is the electromagnetic coil. DETAILED DESCRIPTION OF THE INVENTION

[0025] See Figure 1, which is a direct electromagnetic force testing device for an automotive air-conditioning electromagnetic clutch, includes: a base, a mounting seat, and a fixed shaft. The base, the mounting seat, and the fixed shaft are all made of non-magnetic materials. The base and the mounting seat are both cylindrical. The fixed shaft is slidably fitted in the inner hole of the mounting seat. In this embodiment, the fixed shaft is slidably fitted in the inner hole of the mounting seat through a cage to reduce the sliding resistance between the fixed shaft and the bracket. An installation head is provided at the lower end of the fixed shaft, and the installation head is used to install the armature of the electromagnetic clutch. An annular installation space is provided on the outer peripheral surface of the lower part of the mounting seat for installing the pulley and the electromagnetic coil of the electromagnetic clutch, simulating the installation of the pulley and the electromagnetic coil on the compressor. The base is located directly below the mounting seat, and the inner diameter of the base is larger than the outer diameter of the mounting seat. When the fixed shaft is in the lower limit position, the upper end of the fixed shaft extends out of the inner hole of the mounting seat.

[0026] In this embodiment, a nut is threadedly fitted at the lower end of the annular installation space for axially locking the pulley. A snap ring is sleeved on the upper part of the annular installation space. The snap ring is provided with a positioning projection along the axial direction. A positioning hole is provided on the mounting seat to cooperate with the positioning projection to form circumferential positioning of the snap ring. The snap ring is used to cooperate with the nut to clamp the pulley and the electromagnetic coil.

[0027] The base is used to position the outer gear system part of the pulley suction cup of the electromagnetic clutch, and the inner hole of the base is used to make way for the armature and the fixed shaft. In this embodiment, an annular groove is provided at the upper end of the base for axially and radially positioning the pulley.

[0028] A direct electromagnetic force testing method for an automotive air-conditioning electromagnetic clutch

[0029] S1. Install the pulley, the electromagnetic coil, and the armature on the direct electromagnetic force testing device. In this embodiment, the pulley is installed on the mounting seat through a bearing.

[0030] S2. Install the direct electromagnetic force testing device on the press.

[0031] S3. Energize the electromagnetic coil to make the pulley and the armature (the suction cup part) engage.

[0032] S4. The press presses down on the fixed shaft until the pulley and the armature are separated, and the press pressure is obtained.

[0033] S5. Calculate: the gravity of the fixed shaft + the friction between the fixed shaft and the mounting seat + the press pressure = the electromagnetic force of the electromagnetic clutch, where the friction between the fixed shaft and the mounting seat can be ignored.

[0034] CAE analysis

[0035] To avoid deformation of the pulley during the suction process under the influence of the suction force, which may affect the test results, a non-magnetic material is filled in the air gap on the lower suction surface of the pulley to increase the stiffness of the pulley suction surface. As Figures 2 - 4 shown, if the stiffness of the pulley is not strengthened. Fix the outer edge of the pulley, and the CAE structural analysis diagram at the moment before the driving disc disengages. The deformation amount of each part of the clutch is marked by the color depth. The pulley deformation starts from the first magnetic bridge, and the maximum displacement of the deformation is 0.02 mm (height difference).

[0036] The magnetic potential required for the air gap, that is, the magnetic voltage drop in the air gap,

[0037] is the magnetic induction intensity in the air gap

[0038] where σ is a coefficient;

[0039] l δ is the air gap length (mm);

[0040] A m is the average cross-sectional area of the inner and outer magnetic poles;

[0041] F is the electromagnetic suction force on the suction surface.

[0042] From this analysis: l δ The greater the displacement deformation, the greater the impact on the measurement results. The measured value is on the small side. See the following table:

[0043]

[0044]

[0045] Magnetic flux test analysis

[0046] Between the four poles of the suction surface, embed the detection coil in the armature or the transmission wheel. Pass a current through the detection coil to generate a magnetic flux.

[0047] The magnetic flux passes through the electromagnetic circuit of the clutch and generates an electromagnetic force in the detection coil. Then calculate the magnetic flux according to the electromotive force. Calculate the suction force from the magnetic flux and the magnetic circuit dimensions of the friction surface. According to the measured magnetic flux and the dimensions of the electromagnetic circuit of the friction surface (magnetic pole area), calculate the suction force.

[0048] F = (Φ2 × 105) / (2 × μo × S)

[0049] F: Suction force (N)

[0050] Φ: Magnetic flux (Wb)

[0051] μo: Air permeability (4π × 10-7 H / m)

[0052] S: Pole area (mm2)

[0053] In this embodiment, two test methods for the electromagnetic force of the clutch and one CAE analysis calculation of the electromagnetic force are introduced. Among them, the direct test device for the electromagnetic force of the clutch introduced in this article is invented. The test accuracy of the three schemes is over 90%. See the following table:

[0054]

[0055] Finally, it should be noted that the above preferred embodiments are only used to illustrate the technical solutions of the present invention rather than to limit them. Although the present invention has been described in detail through the above preferred embodiments, those skilled in the art should understand that various changes can be made in form and details without departing from the scope defined by the claims of the present invention.

Claims

1. An electromagnetic force direct test device for an automotive air conditioner electromagnetic clutch, characterized in that, it includes: a base, a mounting seat, and a fixed shaft. The base, the mounting seat, and the fixed shaft are all made of non-magnetic materials. The base and the mounting seat are both cylindrical. The fixed shaft is slidably fitted in the inner hole of the mounting seat. An installation head is provided at the lower end of the fixed shaft, and the installation head is used to install the armature of the electromagnetic clutch. An annular installation space is provided on the outer peripheral surface of the lower part of the mounting seat for installing the pulley and the electromagnetic coil of the electromagnetic clutch. The base is located directly below the mounting seat, and the inner diameter of the base is larger than the outer diameter of the mounting seat. The base is used to position the lower end of the pulley of the electromagnetic clutch, and the inner hole of the base is used to make way for the armature and the fixed shaft; a nut is threadedly fitted at the lower end of the annular installation space for axially locking the pulley; a snap ring is sleeved on the upper part of the annular installation space. The snap ring is provided with a positioning protrusion along the axial direction. A positioning hole is provided on the mounting seat to cooperate with the positioning protrusion to form circumferential positioning of the snap ring. The snap ring is used to cooperate with the nut to clamp the pulley and the electromagnetic coil; an annular groove is provided at the upper end of the base for axially and radially positioning the pulley; a non-magnetic material is filled in the air gap of the lower suction surface of the pulley to increase the stiffness of the suction surface of the pulley.

2. The electromagnetic force direct test device for an automotive air conditioner electromagnetic clutch according to claim 1, characterized in that: when the fixed shaft is at the lower limit position, the upper end of the fixed shaft extends out of the inner hole of the mounting seat.

3. The electromagnetic force direct test device for an automotive air conditioner electromagnetic clutch according to claim 1, characterized in that: the fixed shaft is slidably fitted in the inner hole of the mounting seat through a cage.

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