JPH0756301B2 - Electromagnetic clutch manufacturing method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for manufacturing an electromagnetic clutch, and more particularly to a method for manufacturing an electromagnetic clutch used for driving and stopping a compressor for compressing a refrigerant gas of a car cooler.

(Prior Art) An electromagnetic clutch mainly consists of a fixed electromagnet,
Conventionally, these parts, which are a rotor that rotates while transmitting the magnetic force, that is, a yoke, and a clutch plate that is attracted to the rotor and transmits the rotation to the compressor shaft by frictional force, are conventionally processed by cold forging or punching. It was

The structure of the electromagnetic clutch will be described. In FIG. 1, which is a sectional view of the electromagnetic clutch, reference numeral 1 denotes a drive pulley, which is composed of, for example, a V pulley or a poly V pulley. The rotor or electromagnetic yoke 2 is a ring having a U-shaped cross section and can be freely rotated by a bearing 18. Therefore, this portion is constantly driven by the V-belt during operation of the engine. The bearing 18 is supported on the tip 21 of the compressor. Also, here, the electromagnet support bracket 16
By the coil yoke 14 and the electromagnet by the coil 15,
It is fixed. Reference numeral 20 denotes a compressor drive shaft, and the flange 13 is fixed to the tip thereof. On the flange 13,
The clutch plate 7 is connected by the leaf spring 10.
There are usually three leaf springs 10, and the arrangement is as shown in FIG. By the leaf spring 10, the clutch plate 7 is elastically supported while maintaining a small gap 23 with the yoke 2. With such a configuration, when the electromagnet 15 is energized, the clutch plate 7 is attracted to the yoke 2 and receives the rotation of the yoke 2 as a frictional force to rotate the compressor drive shaft 20 via the spring 10. . As described above, the spring 10 is arranged so that the rotational force acts as it is, and therefore the force acts in the spring pulling direction. More than,
This is an example of a general mechanical structure of an electromagnetic clutch, but this structure is basically valid even for a car cooler.

Next, the electromagnetic action of the conventional electromagnetic clutch will be described. The yoke 2 has the shape shown in FIGS. 3 and 4 and has an arc-shaped elongated hole 24 that interrupts the magnetic path. 5 and 6 show the clutch plate 7, which also has a slot 26 of the same shape. FIG. 7 shows the relationship between the yoke 2 and the clutch plate 7 at the time of attraction, and also shows how magnetic lines of force pass. The left half of the figure shows a portion having arc-shaped elongated holes 24 and 26, and 28 represents the shape of magnetic field lines passing therethrough. As is clear from the figure, since the magnetic force lines 28 cross the adsorption surface, the adsorption force is generated. In order to obtain a strong attracting force, it is desirable that the magnetic force lines pass at right angles to the attracting surface, but in reality, the angle θ is formed. The smaller this angle is, the better. The right half of this figure is mechanically connected 25 and 27 (3rd
(Fig. And Fig. 5), and the magnetic field lines passing therethrough are
It has 29 shapes. This part is not only magnetically ineffective, but repulsive force is generated when the magnetic force lines leak as shown by the dotted line. An even larger negative factor is that the magnetic field lines passing through here reduce the magnetic field lines passing through the effective portion. Therefore, the coil current must be increased to make up for it, and the size of the clutch becomes large.

(Problems to be Solved by the Invention) As described above, in the conventional electromagnetic clutch, the portion forming the passage of the magnetic force lines, that is, the yoke and the clutch plate,
There are some undesirable points in terms of performance. This undesired point has not been overlooked by engineers, but cold forging or punching is adopted for processing these parts from an economical point of view, particularly from the point of economic efficiency in mass production, The undesired point was only accepted, since it was difficult or impossible to eliminate it.

It is an object of the present invention to provide a method capable of eliminating the above-mentioned performance-undesired points existing in the portion forming the passage of the magnetic field lines, and yet achieving it economically.

(Means for Solving the Problems) In order to achieve the above-mentioned object, a method for manufacturing an electromagnetic clutch of the present invention is such that each of a rotor and a clutch plate is molded into a magnetic ring-shaped component by rolling a magnetic material,
The rotor and the clutch are manufactured by forming a non-magnetic material into a non-magnetic ring-shaped component by rolling, alternately nesting the magnetic ring-shaped component and the non-magnetic ring-shaped component, and connecting them to each other. It is characterized in that the plate forms a passage through which the lines of magnetic force pass.

Further, in the method for manufacturing an electromagnetic clutch of the present invention, each of the rotor and the clutch plate is formed into a magnetic ring-shaped component by rounding a magnetic material, and the magnetic ring-shaped components are combined in a nesting manner so that adjacent magnetic ring components are formed. The components may be manufactured by joining them together using a non-magnetic material so that the rotor and the clutch frates form a passage through which the lines of magnetic force pass.

The rounding process is a general term for a process of bending a straight material to make it round.

(Operation) According to the method of manufacturing the electromagnetic clutch of the present invention, the portion forming the passage of the magnetic force line can be configured so as not to have the undesirable point described with reference to the right half of FIG. Its processing cost is significantly lower than that of conventional cold forging or stamping.

(Example) Hereinafter, an example of the present invention will be described in detail in comparison with a conventional method with reference to the drawings.

In the rotor or yoke 2 shown in FIGS. 8 and 9, in order to improve its magnetic performance, conventionally, an arc-shaped elongated hole 24 is used.
Instead of the magnetic path interrupting part constituted by (FIG. 7), nonmagnetic material parts 34, 35 which are spread over the entire circumference are adopted. The parts 31, 32, 33 are made of the same material as conventional yokes. These parts are ring-shaped parts as shown in exploded view in FIG. Similarly, FIGS. 11 and 12 show a clutch plate 7 with improved magnetic performance, which includes parts 41 and 43 made of conventional clutch plate material and a full circumference of non-electromagnetic material. It consists of a spreading part 42. Again, these parts are ring-shaped, as shown in the exploded view of FIG. As described above, if the parts shown in FIGS. 10 and 13 are combined and integrated, a magnetically efficient product can be obtained, but if this is to be achieved by the conventional manufacturing method, Not only the number of parts is increased, but also the number of steps for joining is increased and the amount of materials used is also increased. Therefore, the cost becomes high and it cannot be put to practical use at all. However, according to the finding of the inventor of the present invention, all of these parts can be manufactured by rolling.
By adopting the rounding process, it seems that the current widely used production method of electromagnetic clutches can be completely overturned.

To clarify this point, when the cost is examined, the material cost and the processing cost are major factors that determine the cost. Among them, the material cost can be almost equal to the amount of the material used, and therefore the yield of the material is important with respect to the material cost.

14 and 15 show the yield of the yoke 2 having the conventional structure. Since this yoke is finished by cutting after cold forging, there are restrictions on the processing conditions of cold forging, and a considerable allowance is made. The parallel hatched portion in the figure is a portion to be shaved off.
The yield in this case is about 55 to 65%.

16 and 17 show the yield in the case of the clutch plate 7. This clutch plate is made by punching a plate and machining it, but when punching, the parallel hatched portion becomes scrap. As is clear from this, the yield is extremely poor.

Compared with the one shown in FIG. 14 to FIG. 17, the yield when making the ring-shaped parts by the rounding process is very good. That is, the material before the rounding process is a rectangular plate, and this shape is a shape that is arranged without gaps along the plane, and its formation can be achieved without scrapping parts. In addition, many of the parts that have been precisely processed by rounding do not need to be cut, which also helps improve the yield.

Thus, obviously, the use of rounding significantly reduces material usage.

Equipment depreciation and labor costs have the largest effect on processing costs. Considering the equipment cost, the cold forging currently performed requires a large press, while the rounding process requires a small machine, which is extremely advantageous from the point of equipment depreciation cost. . When considering personnel costs, until recently, it was common for processing man-hours and personnel costs to be in a comparative relationship, and if there were many processing man-hours, labor costs would also rise. According to this, the labor cost is not proportional to the processing man-hour,
Much lower than that. Thus, also in this respect, rounding is advantageous.

As is clear from the above, the rounding process provides a manufacturing method that is magnetically advantageous and has a lower manufacturing cost than the conventional one. Next, an example of a manufacturing method by rounding will be described. There are various examples of rounding, and any of them can be adopted in the present invention. Here, rounding by winding and bending will be described. Since all of them are well-known and widely practiced, they will be briefly described.

FIG. 18 shows the principle of the winding machine. The material 100 is continuously wound by a feed roll 101 and three bending rolls 102, and the rolled product becomes a long coil 103.
A cutting device is attached to this machine, and a ring-shaped part can be obtained by cutting each winding, and a coil spring, for example, can be obtained by cutting with a large number of turns. In this invention, this winding process is suitable for 33, 34,
The part indicated by 35 and 41, 42,
43 and the parts shown.

FIG. 19 conceptually shows a rounding process by bending, which is represented by the process of winding bushes. According to this, for example, a ring-shaped component is obtained from the material 104 shown in FIGS. 20 to 22 through a shape as shown by 105 in FIGS. 23 and 24. This method
It is suitable for processing wide rings.
Parts such as 31 and 32 shown in FIG. 10 are made by such a rounding process.

The product rounded by the above rounding process has a butt portion, not the entire circumference being connected. In the case of mass production, the unattended method of making precise ring-shaped products is to unify the butt parts by upset welding, remove the protrusion of the welding part, and expand to improve the accuracy of the diameter. It can be fully implemented. However, it is not always necessary to weld the abutting portions depending on the way of joining described later. However, in this case, in order to improve the accuracy of the ring-shaped component, a split mold is used as shown in FIGS. 25 and 26 to reduce the rounding diameter. In FIGS. 25 and 26, 106 is a split mold, and 107 is a split mold fastening member. Here, from FIG.
The part indicated by 32 in FIG. 10 is machined.

The above explanation is a method of making a ring-shaped part wound only once, but a method of making a half-turned part as shown in FIGS. 27 to 29 and joining it at two points can also be adopted. . According to this method, all ring-shaped parts can be processed by ordinary press working, so special equipment is not required and upset welding is easier than single winding. Suitable rounding can be achieved.

In order to make the parts shown by reference numerals 31 and 32 in FIGS. 8 to 10, it is necessary to roll the T-shaped last-shaped profile, but the production of the profile requires the premise of mass production of a single product. Therefore, there is a risk that it cannot be implemented due to financial obstacles, and there is a disadvantage that it is a so-called impassable turn.

Secondary processing is required to make these parts from ordinary sheet material without the use of profiles. Figure 30 shows
It is a schematic diagram of a metal mold which makes a T-shaped head by upset processing.
Reference numeral 108 designates a gap that is closed for upsetting, and reference numeral 32 designates the parts shown in FIGS. This processing is obvious from the drawings, so its explanation is omitted,
This processing improves the accuracy of the ring-shaped part. This also has the advantage of eliminating the step of increasing the precision by increasing or reducing the diameter, and thus this processing is more flexible in the production situation than the method of rolling the T-shaped profile.

Next, a method for joining the rolled ring-shaped parts will be described. There are various bonding methods such as a brazing method, a welding method, a mechanical method, and an adhesive method, and therefore, only typical ones will be described here. In addition, in order to bond, it is generally necessary to obtain the shape required for bonding according to the bonding method.

FIG. 31 illustrates secondary processing for bonding by furnace brazing method. Here, the part shown by 33 in FIGS. 8 to 10 is compressed together with cutting to form the inner and outer flanges 33a of the part 33, and the ring-shaped part 33 shown on the left side of this figure is The ring-shaped part has a T-shaped cross section shown on the right side of this figure. FIG. 32 shows a shape temporarily joined for joining by the brazing method in the furnace. Here, since the part 33 is formed in the T-shaped cross section having the flange 33a by the above-mentioned processing, the parts 34 and 35 of the non-magnetic material are replaced by the parts 31 and 32.
If the parts b and c are temporarily attached by projection welding, electric arc welding, or the like, integration can be achieved. In this case, copper is used as the non-magnetic material. Further, the pulley 1 is inserted, and a copper wire ring a is arranged as a brazing material. The thus assembled product is passed through a conveyor-type in-furnace brazing furnace to complete the brazing connection. In this process, the nonmagnetic copper of the components 34 and 35 becomes liquid, but the flange 33a of the component 33 forms the bottom, so that the copper does not flow out. The yokes are joined by brazing as described above, and the yoke is completed when the clutch surface and the bearing insertion portion are finished by cutting. First
Figure 33 shows brazing of the clutch plate, part 41
If a flange is formed inside (FIGS. 11 to 13) in the same manner as 33a described above, connection by brazing can be achieved by the same method as described above. The connection by the brazing method has an advantage that the seam in the abutting portion of the ring-shaped parts is also brazed at the same time. When stainless steel is used as the non-magnetic material in the brazing method, the brazing can be achieved without any problem by inserting a copper brazing material separately.

34 and 35 show the mechanical joining method. In this case, the non-magnetic material component 3 of the ring-shaped components 31, 32, 33
The surface to be contacted with 4, 35 is made uneven by knurling. As the non-magnetic material, those softer than iron materials such as aluminum-based and copper-based metals are used. When this is pressurized and compressed, as shown in FIG. 35,
A strong bond can be obtained by digging into the uneven parts. In this mechanical connection method, it is necessary to use, as the ring-shaped parts 31, 32, 33, those in which the seams of the butt parts are welded. If an adhesive is applied to the knurled uneven portion, a stronger bond can be obtained. This mechanical connection method does not require special equipment like the brazing method,
Further, since the processing is carried out at room temperature, it has a feature that the material is not softened, but it has a drawback that the number of processing steps is increased due to the welding of the joint of the ring-shaped parts and the welding of the pulley in a separate process.

In addition to the above, various bonding methods such as plasma welding method and laser welding method are possible.
It will not be described here because it will change depending on the technical background at that time.

The product combined as described above is completed by the same mechanical finishing as cutting, polishing, etc., but this man-hour can reduce the cutting allowance compared to the conventional one, and it is necessary to cut at all. Since there are no parts, it is extremely small.

Rounding can also be applied to the coil yoke 14. Fig. 36 and Fig. 37 are made of rolled planks or round bars,
Here's how to make it by pushing backwards. In this case, even if the seam is left as it is, the magnetic performance does not change, so that the yield is improved, which is an advantage.

(Advantages of the Invention) The present invention is intended to improve the performance of the electromagnetic clutch by utilizing the characteristics of the electromagnetic clutch for a car cooler and the characteristics of the rounding process, and at the same time, to reduce the manufacturing cost thereof. According to this, the effect of completely changing the current production system of the electromagnetic clutch can be obtained.

[Brief description of drawings]

In all the drawings, for the sake of clarity, the parallel diagonal lines representing the cut surface are omitted. FIG. 1 is an axial sectional view showing a general structure of an electromagnetic clutch. FIG. 2 is a front view corresponding to FIG. FIG. 3 is a front view of a conventional electromagnetic yoke. FIG. 4 is a sectional view taken along the line IV-IV in FIG. FIG. 5 is a front view of a conventional clutch plate. FIG. 6 is a sectional view taken along line VI-VI in FIG.
FIG. 7 shows magnetic field lines in a conventional yoke and clutch plate. FIG. 8 is a front view of the improved yoke. FIG. 9 is an axial sectional view corresponding to FIG. First
FIG. 10 is an exploded view corresponding to FIGS. 8 and 9.
FIG. 11 is a front view of half of the improved clutch plate. FIG. 12 is an axial sectional view corresponding to FIG. 11. FIG. 13 is an exploded view corresponding to FIGS. 11 and 12. 14 and 15 show the material yield in the yoke. 16 and 17 show the material yield in the conventional clutch plate. FIG. 18 shows the principle of rounding by winding. 19 to 24 show the principle of rounding by bending. Figure 25 shows
It is an axial sectional view of a split mold. FIG. 26 is a horizontal sectional view corresponding to FIG. 25. 27 to 29 show a half-wound part and its welding. FIG. 30 is an axial sectional view of a mold for forming a T-shaped head. FIG. 31 illustrates secondary processing for brazing with a furnace. FIG. 32 shows a temporary joining state of yokes for brazing in the furnace. FIG. 33 shows a temporary engagement state of clutch plates for brazing in the furnace. 34 and 35 represent mechanical coupling. Figure 36 and
Figure 37 shows the case where rounding is applied to the coil yoke. In the drawing, 2 is an electromagnetic yoke, 7 is a clutch plate,
Each of the ring-shaped parts in the electromagnetic yoke of 31 to 35,
41 to 43 show each of the ring-shaped parts of the clutch plate.

Claims (2)

[Claims] 1. A rotor and a clutch plate each of which is formed by rolling a magnetic material into a magnetic ring-shaped component, and by rolling a non-magnetic material into a non-magnetic ring-shaped component. A method for manufacturing an electromagnetic clutch, characterized in that magnetic ring-shaped parts are alternately combined in a nested manner, and they are connected to each other to form a passage through which magnetic lines of force are formed by the rotor and the clutch plate. 2. A rotor and a clutch plate, each of which is formed by rolling a magnetic material into a magnetic ring-shaped component, and the magnetic ring-shaped components are combined in a nesting manner, and adjacent magnetic ring-shaped components are made of a non-magnetic material. And a clutch plate to form a passage through which a magnetic line of force passes.