JPH051668Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a compressor having a function of detecting rotation speed, and particularly to an abnormality detection mechanism for detecting an abnormality in the compressor.

(Prior Art) Generally, when a car air conditioner compressor stops due to seizure or other causes, the connection between the drive source (engine) and the compressor is quickly turned off.
It is necessary to prevent damage to drive elements, etc. Especially if not only the compressor but also other equipment such as an alternator is driven by a single belt, if the compressor is damaged, turn off the electromagnetic clutch to prevent it from affecting the operation of other equipment. There is a need. For this reason, the compressor is usually provided with a sensor for detecting the rotation speed of the compressor.

Conventionally, in order to detect the rotation speed of a compressor, a rotating body is connected to the main shaft, the leakage magnetic flux from an electromagnetic clutch is used to change the magnetic flux generated in the rotating body as the rotating body rotates, and this change is detected as a sensor. It is detected by turning. Then, the rotation speed of the compressor is obtained based on the output from this sensor, and when the rotation speed becomes less than a predetermined value, the drive source and the compressor are disconnected.

(Problems that the invention aims to solve) By the way, in the conventional compressor abnormality detection mechanism, a rotating body must be connected to the main shaft and a sensor must be attached to the compressor casing, making the configuration complicated. There is a point. Furthermore, depending on the type of compressor, it may not be possible to connect the rotating body, and there is also the problem that a hole for mounting a sensor must be newly provided in the compressor.

An object of the present invention is to provide an abnormality detection mechanism that has a simple configuration and is applicable to all compressors.

(Means for Solving the Problems) According to the present invention, the compressor housing is provided with a cylinder chamber in which fluid is compressed, and fluid is sucked into the cylinder chamber or fluid is drawn from the cylinder chamber depending on the compression stroke. In a compressor that has a valve mechanism that automatically opens and closes the cylinder chamber in order to discharge The valve mechanism constitutes a contact switch, and has a detection means for detecting conduction and non-conduction of the valve mechanism, and this detection means There is obtained a compressor abnormality detection mechanism characterized in that the compression operation of the compressor is stopped when conduction and non-conduction continue.

(Example) The present invention will be explained below using examples shown in the drawings.

First, referring to FIG. 1 showing an oscillating compressor to which the present invention is applied, 1 is a cylindrical casing.
A cylinder block 2 having cylinder bores 2a arranged at equal angular intervals around the center line of the cylindrical casing 1 is disposed at one end of the casing 1.

A valve plate 3 having a suction hole 3a and a discharge hole b formed therein is superposed on the end face of the cylinder block 2 via a gasket 4' and a suction valve 5. The valve plate 3
A cylinder head 6 which defines a suction chamber 7 and a discharge chamber 8 is placed on the cylinder block 2 through an insulating gasket 4 to close the end face of the cylinder block 2.

The gaskets 4' and 4, the valve plate 3, the suction valve 5 and the cylinder head 6 are fixed by fixing bolts 9 which pass through each part and are screwed into the cylindrical casing 1.

Further, an electrically conductive discharge valve 10 is disposed above the discharge hole 3b formed on the valve plate 3 to open and close the discharge hole 3b, and the discharge valve 10 defines the opening degree of the discharge valve 10. It is fixed to the valve plate 3 together with the retainer 11 by fixing bolts 12. The suction hole 3a and the discharge hole 3b are opened and closed by a pressure difference between the inside of the cylinder bore 2a and the suction chamber 7 and discharge chamber 8 of the cylinder head 6. The other end of the cylindrical casing 1 is closed by a front housing 14 having a radial needle bearing 13 disposed in a part of an opening formed in the center. In this way, a crank chamber 1a is formed between the cylinder block 2 and the inner wall surface of the front housing 14. The crank chamber 1a has a built-in motion conversion mechanism as described below. A main shaft 15 is disposed in the front housing 14 so as to pass through the opening thereof. The main shaft 15 is a radial needle bearing 13
It is supported by the front housing 14 by. A wedge-shaped rotor 16 is fixed to the inner end of the main shaft 15. On the inclined surface side of the wedge-shaped rotor 16, a swing plate 18 having a bevel gear 17 fixed to the center thereof is disposed. The bevel gear 17 is received by a bevel gear 19 fixed to the cylinder lock 2 via a steel ball 20. Both bevel gears 17 and 19 have the same number of teeth and mesh with each other. Furthermore, the rocking plate 18
One end of a rod 21 is ball-connected to the periphery of the rod. The other end of the rod 21 is connected to a piston 22 disposed within the cylinder 2a. When the main shaft 15 rotates, the swing plate 18 swings around the steel ball 20 without rotating, and the piston 22
is reciprocated within the cylinder bore 2a. piston 2
2, the suction valve 5 and the discharge valve 10
opens and closes, and the cylinder bore 2 is opened and closed from the suction hole 3a.
The refrigerant gas sucked into a is compressed and discharged through the discharge hole 3.
It is discharged from b.

Here, referring to FIG. 2, an insulating gasket 4 is attached to the valve plate 3 except for the valve seat portion 3c at the outlet end of the discharge hole 3b, and a fixing bolt 1 is attached to the valve plate 3.
The lower surface of the head 2 and the upper side of the fixing bolt 12 are covered with an insulating material 10a. That is, the discharge valve 10 and the discharge valve retainer 11 are insulated from the fixing bolt 12, that is, the compressor housing (conductive), by the insulating material 10a. On the other hand, as shown in the figure, a part of the discharge valve 10 is in direct contact with the valve seat 3c when the discharge hole 3b is closed, and although not shown, when the discharge hole 3b is opened, a part thereof is in direct contact with the valve seat 3c. It does not come into direct contact with the valve seat portion 3c. That is, the discharge valve 10 and the valve seat portion 3c (ie, the compressor housing) are insulated by the insulating gasket 4. Furthermore, the discharge valve 1
A lead wire 10b is connected to one end (left end) of 0, and a lead wire (not shown) is also connected to the compressor casing.
is connected.

Here, referring to FIG. 3, the discharge valve 10 is connected to the waveform shaping circuit 2 via a DC power supply 23 by a lead wire.
4, while the compressor housing is connected to a waveform shaping circuit 24 by a lead wire. Therefore,
The discharge valve 10 will act as a contact switch. The waveform shaping circuit 24 is connected to a pulse presence/absence determination circuit 25, and the pulse presence/absence determination circuit 25 is connected to a driver circuit 26 and a switch circuit 27. On the other hand, the driver circuit 26 is connected to a thermo circuit (not shown) and a switch circuit 27.
It is connected to the. A battery (not shown) is connected to this switch circuit 27, as well as an electromagnetic coil 28 of an electromagnetic clutch.

In the case of a compressor having a plurality of discharge valves, only one of the discharge valves is a contact switch, and the other discharge valves are completely insulated.

When the compressor operates, the discharge valve 10 repeats opening and closing according to the speed of the reciprocating movement of the piston 22, that is, according to the rotational speed of the main shaft 15. Discharge valve 1
When the discharge hole 3b is closed by the discharge valve 10, a DC voltage is applied to the waveform shaping circuit 24, and when the discharge hole 3b is opened by the discharge valve 10, a DC voltage is applied to the waveform shaping circuit 24. No voltage is applied. That is, the discharge valve 10 functions as a contact switch, and is repeatedly turned on and off by opening and closing the discharge valve 10, and a pulse voltage is input to the waveform shaping circuit 24.

This pulse voltage is input to the waveform shaping circuit 24, shaped, and then input to the pulse presence/absence determination circuit 25. By the way, the number of pulse voltage pulses within a predetermined time is synchronized with the rotation speed of the main shaft 15, and the pulse presence/absence determination circuit 25 issues an abnormality detection signal when the number of pulses within a predetermined time is less than a predetermined number. In response to this abnormality detection signal, the switch circuit 27 is operated to disconnect the battery and the electromagnetic coil 28. This turns the electromagnetic clutch off and disconnects the compressor from the drive source.

In addition, in order to prevent the electromagnetic clutch from repeatedly turning on and off due to the turning on and off of the thermo switch that detects the evaporator outlet temperature to prevent excessive cold and frost formation, the driver circuit 2
6 sends a thermoswitch signal to the pulse presence/absence determination circuit 25, whereby the pulse presence/absence determination circuit 25 knows that the compressor has been stopped and does not determine that the compressor is abnormal.

In this way, in the above-described embodiment, since the rotation speed of the compressor is detected by opening and closing the discharge valve 10, there is no need to newly provide a rotating body and a sensor to the compressor as in the conventional case, and the configuration is simplified. It becomes extremely easy. In the above embodiment, the rotation speed of the compressor is detected by opening and closing the discharge valve, but the rotation speed of the compressor may be similarly detected by opening and closing the suction valve. Furthermore, although the above-mentioned embodiments have been described with respect to a swing type compressor, it goes without saying that the present invention can also be applied to other compressors such as a scroll type compressor.

(Effects of the invention) As explained above, according to the compressor abnormality detection mechanism according to the invention, there is no need to newly provide a rotating body and sensor to the compressor as in the conventional case, so the configuration is extremely simple. It has the advantage of being applicable to all compressors.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view showing a rocking compressor to which the abnormality detection mechanism according to the present invention is applied, Fig. 2 is a cross-sectional view showing the mounting structure of the discharge valve, and Fig. 3 is a cross-sectional view showing the mounting structure of the discharge valve. FIG. 2 is a diagram showing an example of a detection circuit. DESCRIPTION OF SYMBOLS 1...Casing, 2...Cylinder block, 3...Valve plate, 4...Insulating gasket, 5...
...Suction valve, 6...Cylinder head, 7...Suction chamber, 8...Discharge chamber, 10...Discharge valve, 11...Discharge valve retainer, 12...Fixing bolt, 14...Front housing, 15... Main shaft, 16... Wedge-shaped rotor, 17, 19... Bevel gear, 18... Rocking plate, 20... Steel ball, 21... Rod, 22... Piston, 23... DC power supply, 24... Waveform shaping Circuit, 25... Pulse presence/absence determination circuit, 26... Driver circuit, 27... Switch circuit, 28... Electromagnetic coil.

Claims (1)

[Scope of utility model registration request] A compressor housing having a cylinder chamber in which fluid is compressed, and for automatically opening and closing the cylinder chamber to suck fluid into the cylinder chamber or discharge fluid from the cylinder chamber according to a compression stroke. In a compressor having a valve mechanism, a voltage is applied to the valve mechanism, and the valve mechanism is insulated from the compressor casing in an open state and electrically connected to the compressor casing in a closed state. A contact switch is constituted by a valve mechanism, and has a detection means for detecting conduction and non-conduction of the valve mechanism, and the detection means detects the compression operation of the compressor when the conduction and non-conduction continue for a predetermined period of time. An abnormality detection mechanism for a compressor, characterized in that the compressor is stopped.