Compressor

Abstract

This compressor includes housing members that form a body; a drive shaft linked to a drive power source via an electromagnetic clutch; movable members moving in cooperation with the drive shaft and carrying out the compression of a fluid; a detected body moving in cooperation with the drive shaft; a drain bolt screwed into a drain bolt hole provided in a housing member in proximity to the detected body; and a detecting device detecting the rotation state of the drive shaft by the detected body. The drain bolt is provided with a permanent magnet, the detecting device is structured by a magnetic sensor that includes a magnetic impedance element, and the magnetic sensor is provided at the head portion of the drain bolt. Thereby, it is possible to provide a rotation detecting mechanism by using an existing drain bolt, without requiring the machining of a hole in the compressor body.

Description

BACKGROUND OF THE INVENTION[0001]1. Field of the Invention[0002]The present invention relates to compressors for vehicle air conditioners, and in particular, relates to a compressor that can be provided with a rotation detecting mechanism that does not require the machining of a hole in the compressor body only in order to provide the rotation detecting mechanism, and that is compact and inexpensively manufactured.[0003]2. Description of the Related Art[0004]Conventionally, compressors for vehicle air conditioners are known that are provided with a rotation detecting mechanism in order to detect rotation malfunctions due to seizing and the like. For example, as shown in FIG. 19, in this rotation detecting mechanism, a through hole 102 is formed in a non-magnetic housing member 101, and a detecting sensor 104 is mounted in this through hole 102 via an O-ring 103. In addition, the change in the magnetic flux that flows from the magnet 106 to the core 107 accompanying the rotation of a...

AI Technical Summary

Benefits of technology

[0029]According to the compressor of the present invention, the rotation state of the compressor is detected by providing a permanent magnet on a drain bolt, which is normally provided, in order to form a circulating magnetic circuit via the drain bolt, and by detecting the magnetic flux changes in this circulating magnetic circuit from the outside of the housing member by using a magnetic sensor that is provided at the head portion of the drain bolt. Thereby, it is possible to provide a rotation detecting mechanism by using a pre-existing drain bolt hole, without requiring the machining of a hole in the compressor body in order to provide a detecting device, and it is possible thereby to provide a compact and inexpensively manufactured compressor. In addition, because the detecting device is positioned on the outside of the housing member, it is not necessary to protect the detecting device from pressure. Additionally, because it is possible to avoid the inclusion of contaminants that accompanies the placement of the detecting device, it is possible to provide a compact and inexpensively manufactured compressor.

[0030]In addition, in the case in which a circulating magnetic circuit, which is due to the magnetic flux of a permanent magnet, is conducted through the detected body and the drain bolt, it is possible to form a stronger circulating magnetic circuit, and it is possible thereby to detect the magnetic flux changes in the circulating magnetic circuit more reliably.

[0031]Furthermore, in the case in which the permanent magnet is provided at the distal end of the drain bolt, it is possible to form a stronger circulating magnetic circuit, and it is possible thereby to detect the magnetic flux changes in the circulating magnetic circuit more reliably.

[0032]In addition, in the case in which the permanent magnet is provided at the head portion of the drain bolt, it is possible to form a stronger circulating magnetic circuit, and it is possible thereby to detect the magnetic flux changes in the circulating magnetic circuit more reliably.

[0033]Furthermore, in the case in which the detecting device is provided with a magnetic member that covers the head portion of the drain bolt, it is possible to form a stronger circulating magnetic circuit, and it is possible thereby to detect the magnetic flux changes in the circulating magnetic circuit more reliably.

[0034]According to the compressor of the present invention, the magnetic flux from a magnet that is provided in a detected body forms a circulating magnetic circuit via a drain bolt, and the rotation state of the compressor is detected by detecting the magnetic flux changes in this circulating magnetic circuit from the outside of the housing member by using a magnetic sensor that is provided at the head portion of the drain bolt. Thereby, it is possible to provide a rotation detecting mechanism by using a pre-existing drain bolt hole without requiring the machining of a hole in the compressor body in order to provide the detecting device, and it is possible thereby to provide a compact and inexpensively manufactured compressor. In addition, because the detecting device is positioned on the outside of the housing member, it is not necessary to protect the detecting device from high pressure. Additionally, because it is possible to avoid the inclusion of contaminants that accompanies the placement of the detecting device, it is possible to provide thereby a compact and inexpensively manufactured compressor.

Problems solved by technology

However, in this conventional rotation detecting mechanism, it is necessary to form the through hole 102 by machining a hole in the housing member 101, and the production cost of the compressor is thereby increased.

In addition, a sealing structure that uses the O-ring 103 is necessary, and this further increases the production cost.

Furthermore, there are problems in that, for example, contaminants that adhere to the detecting sensor104 may enter into the compressor, and there is thus the possibility of seizing of the compressor.

JP-A-H6-299960, the magnetic sensor is placed at the head portion of the fastening fixtures or on the stator side of an electromagnetic clutch that is opposite to the fastening fixtures, and there is a problem in that the overall length of the compressor in the axial direction is increased due to the space for the sensor installation.

Furthermore, in order to amplify the magnetic flux, which takes the form of a large circulating magnetic flux circuit, a strong and high cost magnet is necessary.

For these reasons, there is the problem, for example, that the production cost of the compressor is increased.

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