JPH0533250Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a holder for holding a ferrite permanent magnet for use in a motor when both sides of the magnet are being ground.

[Prior art and its problems] As is well known, ferrite magnets for motors are made by molding powder whose main component is ferric oxide into an arc plate shape and sintering it. A pair of them is arranged inside the rotor so as to sandwich the rotor from both sides. Therefore, ferrite magnets are required to have high dimensional accuracy in order to maintain the gap with the rotor, but since this accuracy varies greatly depending on sintering conditions, material variations, etc., ferrite magnets have traditionally been used to maintain this accuracy. The outer and inner surfaces of the magnet were ground using a grinder equipped with a diamond grindstone. However, in the conventional grinding method, ferrite magnets are arranged in a row and are sandwiched from above and below by rubber rollers and sent to a rotating grindstone. However, in this method, if the end face of each ferrite magnet is deformed, the ferrite magnet is fed obliquely to the rotating grindstone, making it impossible to obtain the required grinding accuracy. In other words, in the conventional method, ferrite magnets are arranged in a line and the following ferrite magnet pushes the preceding ferrite magnet and sends it to the rotating grinding wheel. Therefore, the grinding accuracy may be affected by the poor shape of the pressed end surface of each ferrite magnet. There was a problem.

In addition, the grinding jig disclosed in Japanese Utility Model Application No. 59-28447 has a plurality of ferrite magnets arranged in a straight line on a convex arcuate surface and the upper surface of the ferrite magnets is brought into contact with a grinding wheel. It is possible to grind the magnets at the same time, but even in this case, if the end face shape of each ferrite magnet is poor, the linear alignment will collapse when longitudinal force is applied due to contact with the grinding wheel, resulting in poor grinding accuracy. There was a risk that the condition would worsen or that suction and holding by vacuum would no longer be possible.

[Means for Solving the Problems] The present invention is an attempt to solve the above problems, and involves grinding a plurality of ferrite magnets when grinding the outer and inner surfaces of a substantially arc plate-shaped ferrite magnet using a rotating grindstone. A ferrite magnet grinding holder for holding them in a straight line, consisting of a lower holder and an upper holder, the lower holder having an upper surface shaped into a convex arcuate surface matching the inner surface shape of the ferrite magnet
Forming strip-like raised portions on the upper surface at regular intervals in the longitudinal direction with a height of less than half the thickness of the ferrite magnet, thereby forming a partitioned space in which one ferrite magnet is placed between the strip-like raised portions; Furthermore, a vacuum suction hole that opens into each compartment space is formed, and the lower surface of the upper holder is formed into a concave arc surface that matches the outer shape of the ferrite magnet, and a similar band-shaped ridge is formed on the lower surface to form the compartment spaces. This ferrite magnet grinding holder is characterized by having vacuum suction holes opened in each of the divided spaces.

[Example] Next, an example of the present invention will be described with reference to the drawings.
First, to explain the whole of this grinding device, in the figure, 1 and 2 are a first rotary whetstone and a second rotary whetstone that rotate in the same vertical plane. It is rotatably supported by bearing bodies 3 and 4, respectively. The bearing bodies 3 and 4 are provided with linear bearings 8 that slide on guide rails 6 and 7 provided on both sides of the machine base 5. The heights of the rotary grindstones 1 and 2 can be adjusted by slightly moving them up and down. 9 is a motor provided on the machine base 5 to rotate the second rotating grindstone 2, and 10 is a rotation transmission belt thereof. A similar motor for rotating the first rotating grindstone 1 is provided directly below the motor 9, and 11 is its rotation transmission belt. Also, 1
Nozzles 2 and 13 spray low-pressure or high-pressure cooling water onto both rotating grindstones 1 and 2, and 14 and 15 are covers for preventing splashing of water.

Two rails 1 are placed horizontally and parallel to each other on the table 16 placed below the rotating grindstone 1.
7, 17, and linear bearings 19, 19 that slide on the rails are provided on the reciprocating table 18, and a long stroke hydraulic cylinder 20 is provided between the rails 17, 17, and the operating rod end of the hydraulic cylinder 20 is installed. A bracket 47 is fixed to one end of the carriage 18.
The reciprocating carriage 18 is reciprocated along the rails 17, 17 by the operation of the hydraulic cylinder 20. 21 is the lower holder shown in FIG. 6, and the lower holder 21 is mounted with bolts on the carriage 18 so that it can reciprocate horizontally within the same vertical plane as the rotary grindstones 1 and 2 due to the reciprocation of the carriage 18. 45. The lower holder 21 holds a plurality of substantially arc plate-shaped ferrite magnets a, a..., which are ground objects, in a row with their arc-shaped convex surfaces facing upward.
The upper surface of the ferrite magnet a is formed into a convex arcuate surface that matches the inner surface shape of the ferrite magnet a, and by forming band-shaped raised portions 22, 22, . . . at regular intervals in the longitudinal direction on the upper surface, the ferrite magnet a is It forms compartment spaces 23, 23, . . . in which one piece can be placed.
The height of the band-shaped raised portions 22, 22, . . . is set to be less than half the thickness of the ferrite magnet a. Reference numerals 24, 24, . . . are vacuum suction holes opening into the respective compartment spaces, and each vacuum suction hole is connected to a vacuum pump via a valve (not shown).

On the other hand, rails 26, 26 are disposed on the lower surfaces of the horizontal columns 25, 25, which are horizontally installed above the second grinding wheel 2, so that the rails 26, 26
The reciprocating table 27 is provided with linear bearings 28, 28 for sliding. 29 connects the carriage 27 to rails 26, 26
A hydraulic cylinder is fixed to a part of the machine frame 30 in order to reciprocate along the reciprocating table.The operating rod 31 of the hydraulic cylinder is fixed to a bracket 33 fixed to one side of a case 32 that covers the upper part of the reciprocating table 27. It is worn. An air cylinder 34 is vertically provided in the center of the carriage 27, and bearings 35, 35 are provided on both sides of the air cylinder 34. The lifting table 37 is connected to the operating rod 36 of the air cylinder 34.
The lifting table 37 is suspended from the air cylinder 34
It moves up and down by the operation of. 38, 38 are guide rods established on the lifting table, and the guide rods are inserted through the bearings 35, 35 to keep the lifting table 37 horizontal.
Reference numerals 39 and 39 designate stoppers for positioning the rising end, which are fixed to the upper surface of both ends of the lifting table 37. An upper holder 40 is fixed to the lower surface of the lifting table 37 with bolts 46 so as to be located in the same vertical plane as the rotary grindstones 1 and 2. As shown in FIG. 7, the upper holder 40 is formed into a concave arc surface that matches the arc convex surfaces of the ferrite magnets a, a, etc., and the concave arc surface is provided with band-like protuberances 41, 41 at regular intervals in the longitudinal direction. ... are formed, and partitioned spaces 42, 42, ..., in which one ferrite magnet a is accommodated, are formed between the band-like raised portions. Vacuum suction holes 43, 43, . . . are opened in each of the divided spaces 42, 42, . The height of the band-shaped raised portions 41, 41, . . . is set to be less than half the thickness of the ferrite magnet a. Reference numeral 44 indicates a belt conveyor for carrying out the ferrite magnets a, a after grinding.

In the double-sided grinding device for ferrite magnets configured in this way, each compartment space 2 on the lower holder 21 is
Ferrite magnets a, a... are arranged at 3, 23...,
By communicating the vacuum suction holes 24, 24, . . . with a vacuum pump, the ferrite magnets a, a, . . . are firmly and immovably adsorbed thereto. Then, by extending the operating rod of the hydraulic cylinder 20 and moving the carriage 18 along the rails 17, 17, the ferrite magnets a, a held on the lower holder 21 are
The upper surface of... is ground by the first rotating grindstone 1. 1st
The rotary grindstone 1 has ferrite magnets a, a on its outer peripheral surface.
It is formed into an arcuate concave surface that matches the outer surface of the ferrite magnets a, a, and so on, so that the outer surfaces of the ferrite magnets a, a, and so on can be ground into a predetermined shape. The ferrite magnets a, a, etc. ground in this manner are
It moves and stops. On the other hand, the upper holder 40 is stopped directly above the ferrite magnets a, a, . And the vacuum intake holes 24, 24 of the lower holder 21
At the same time, the attraction of the ferrite magnets a, a... by the upper holder 40 is released, and the vacuum attraction hole 43 of the upper holder 40,
43... to attract the ferrite magnets a, a.... At this time, the band-shaped raised parts 22, 22... and the band-shaped raised parts 44, 44... are each made of a ferrite magnet a.
The outer surface of the ferrite magnet a does not touch the lower holder 40 when the holders 21 and 40 are brought into alignment, without colliding.
Since it is in close contact with the concave arcuate surface, the vacuum suction force acts reliably. Then, the upper holder 40 is raised and stopped at that height by the stoppers 39, 39. Subsequently, by contracting the actuating rod 31 of the hydraulic cylinder 29 and moving the carriage 27 to the right in FIG. Grind. The outer circumferential surface of the second rotating grindstone 2 is formed into an arc shape in accordance with the required grinding shape of the inner surfaces of the ferrite magnets a, a..., thereby making it possible to finish the inner surfaces of the ferrite magnets a, a... with high precision. . The ferrite magnets a, a, .

[Effects of the Invention] As described in the embodiments above, the present invention consists of a lower holder and an upper holder for grinding both sides of a ferrite magnet, the lower holder has a convex arc surface, and the upper holder has a concave arc surface. Both holders have partitioned spaces formed by band-like ridges so that each ferrite magnet can be accommodated, so even if the ferrite magnets are lined up in a straight line, individual ferrite magnets will not come into contact with each other. This has the advantage that individual ferrite magnets can be ground with high precision without being affected by the degree of deformation of the end faces of adjacent ferrite magnets because they can be reliably held in the divided space by vacuum suction and ground. .

[Brief explanation of the drawing]

The drawing shows one embodiment of the present invention.
The figure is a side view of the entire double-sided grinding device, Figure 2 is its top view, Figure 3 is an enlarged cross-sectional view of Figure 1, Figure 4 is an enlarged view of the main parts of Figure 1, and Figure 5 is a view of the holder. A cross-sectional view, FIG. 6 is a perspective view of the lower holder, and FIG. 7 is a perspective view of the upper holder. a... Ferrite magnet, 1, 2... Rotary grindstone,
21...Lower holder, 22...Band-shaped raised portion, 23...
...Division space, 24...Vacuum suction hole, 40...
Upper holder, 41...band-shaped raised portion, 42...divided space, 43...vacuum suction hole.

Claims (1)

[Scope of utility model registration request] A ferrite magnet grinding holder for holding a plurality of ferrite magnets lined up in a straight line when grinding the outer and inner surfaces of substantially arc plate-shaped ferrite magnets using a rotating grindstone, the holder comprises a lower holder and an upper holder. The upper surface of the lower holder is shaped into a convex arc surface that matches the inner shape of the ferrite magnet.
Forming strip-like raised portions on the upper surface at regular intervals in the longitudinal direction with a height of less than half the thickness of the ferrite magnet, thereby forming a partitioned space in which one ferrite magnet is placed between the strip-like raised portions; Furthermore, a vacuum suction hole that opens into each compartment space is formed, and the lower surface of the upper holder is formed into a concave arc surface that matches the outer shape of the ferrite magnet, and a similar band-shaped ridge is formed on the lower surface to form the compartment spaces. A ferrite magnet grinding holder characterized in that vacuum suction holes are provided in each compartment space.