JPH0441178A - Grinding machine rest device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an improvement of a rest device used for steadying a workpiece in a grinding machine.

(Conventional technology) Conventionally, in a grinding machine that grinds a workpiece with a grinding wheel, especially when processing a workpiece that is long and thin compared to its diameter,
A rest device may be used to support the intermediate portion and prevent deformation. Such rest devices are known, for example, as shown in Utility Model Publication No. 53-31508 and Utility Model Publication No. 59-9308, but the outline of the structure of the device is as shown in Fig. 4. It is.

For example, when grinding the outer periphery of a cylindrical workpiece W with the rotating grinding wheel 51, the axes of both shaft ends of the workpiece W are
It is rotatably held around a central axis P by the center of a headstock and the center of a tailstock (not shown), and the intermediate portion is supported by a rest device 52. This rest device 52 includes a first sliding rod 54 and a second sliding rod that are horizontally slidable with respect to the main body 53.
A sliding rod 55 is provided, and an upper contact 57 is provided at the front end of the first sliding rod 54. On the other hand, the second sliding rod 5
The front end of 5 is connected by a connecting pin 60 to an L-shaped arm 59 that is pivoted to a fulcrum 58 on the upper part of the main body 53, and a lower contact 61 is provided at the upper tip of the L-shaped arm 59. The upper contact 57 supports the side of the work W, and the lower contact 61 supports the lower part of the work W.

On the rear end side of each sliding rod 54.55, feed screw members 63.64 with opposite threads are screwed together, and each of the feed screw members 63.64 is provided with a gear 65.66. They mesh with each other. This gear 65 is driven by a stepping motor 69 via a gear train and a reduction gear 68.
be rotated.

Therefore, the gear 6 is operated by the stepping motor 69.
5 rotates forward and the first sliding rod 54 moves forward, the gear 66 rotates in the opposite direction and the second sliding rod 55 also moves forward, supporting the outer periphery of the workpiece W to be ground in a fixed position and feeding the workpiece W. I also make sure to do the same.

(Problem to be Solved by the Invention) However, in the case of the above-mentioned device, the gear ratio of the gears 65 and 66 is constant, so the amount of movement of the first sliding rod 54 and the amount of movement of the second sliding rod 55 are always the same. The first is that it moves at a constant rate.
The problem of an error occurring between the amount of movement of the upper contactor 57 attached to the sliding rod 54 and the amount of movement of the lower contactor 61 swinging via the L-shaped arm 59 has been solved.

That is, the upper contactor 57 is horizontally displaced by a predetermined amount together with the first sliding rod 54, but the lower contactor 61 does not undergo a vertical displacement proportional to the horizontal displacement amount, and therefore the work W
The distance from the center of rotation P to each contact 57.61 was incorrect.

Therefore, in the case of the above-mentioned device, if the model of the workpiece W to be handled is changed and the outer diameter becomes different, an error will occur between the contacts and the workpiece, and it will be necessary to change to a different contactor. Otherwise, it was necessary to readjust the position using the position adjustment screw 70.

Furthermore, in order to move the first sliding rod 54 and the second sliding rod 55 forward or backward together, the feed screw members 63 and 64 had to be reverse-threaded, which caused the problem that the parts were not compatible. .

(Means for Solving the Problems) In order to solve the problems, the present invention provides a first arm having an upper contact and a second arm having a lower contact, and also provides two arms that swing around the same swing fulcrum. The swing fulcrum was set at a position where the distance between the upper contact and the lower contact was equal to -.

Further, a biasing member is interposed between the first arm and the second arm,
Each arm was biased either in the direction of separation or in the direction of approach.

(Function) The oscillation wJjE, that is, the amount of horizontal and vertical movement of the upper contact and lower contact that oscillate around the oscillation fulcrum, is always constant,
Even if the diameter of the workpiece changes, there will be no error in the distance from the center of rotation. Further, by interposing the biasing member between the arms, the error due to backlash is absorbed, further improving accuracy.

(Example) An example of the rest device of the present invention will be described based on the attached drawings.

FIG. 1 is a partially cutaway side view of the rest device of the present invention;
FIG. 2 is an operational view of the distal arm portion, and FIG. 3 is an enlarged view of the biasing member.

As shown in FIG. 1, the rest device 1 of the present invention is used when processing the outer periphery of an elongated cylindrical workpiece W, such as a crankshaft, with a grinding wheel 2, and is used to Both shaft ends are held by the center of the pusher,
It is configured to support the intermediate portion of a workpiece W that is rotatable around a central axis P.

This rest device 1 includes a device main body 3 and two horizontal screw shafts 4 and 5 built into the device main body 3 via bearings, and a driven gear 6 is provided on the upper screw shaft 4. The drive shaft 8 is rotated by a servo motor (not shown), and receives the rotational driving force of the drive shaft 8. Further, a gear 9 for meshing with the gear 10 of the lower screw shaft 5 is also provided next to the gear 6, so that the rotation of the upper screw shaft 4 is transmitted to the lower screw shaft 5.

Each screw shaft 4.5 is provided with a fine adjustment mechanism. That is, screws i4a, 5a are provided at the core portions of the screw shafts 4, 5, and fine adjustment members 11, 12 are provided at the extending portions of the threaded rods 4a, 5a that protrude rearward from the device body 3. are screwed together. Moreover, on the tip side of these threaded rods 4a, 5a, m
Adjustment screw portions 13 and 14 are provided, as well as an operating screw portion 15°1 for screwing into sliding rods 18 and 19, which will be described later.
6 is provided. For this reason, the adjustment nut member 11
．． By rotating 12, the threaded rods 4a and 5a move forward and backward, and the positions of the sliding rods 18 and 19 described below can be slightly moved forward and backward, and the drive shaft 8 is rotated by a servo motor (not shown). It is also possible to change the position of each sliding rod 1B, 19.

A first arm 21 is connected via a connecting pin 20 to the tip of the first sliding rod 18 that is screwed onto the threaded rod 4a of the upper screw shaft 4, and is also screwed onto the threaded portion 5a of the lower screw shaft 5. A second arm 2 is connected to the tip of the second sliding rod 19 via a connecting pin 22.
3 are connected. and each of these arms 21.23
A common rocking bin 24 is attached to the lower end of the device body 3.
It is pivoted on the side and can swing freely around the swing bin 24. Further, an upper contact 26 and a lower contact 27 for abutting and holding the workpiece W are provided on the tip side of each arm 21, 23, and are detachable. That is, the upper contactor 26 can contact the outer circumference of the workpiece W from the side in a substantially horizontal direction, and the lower contactor 27 can contact the outer circumference of the workpiece W from below in a substantially vertical direction. , to support the workpiece W so that it does not bend.

On the other hand, as shown in FIG. 2, the swing pin 24 is arranged in a direction that divides the direction of each contact 26.27 into two equal parts from the central axis P of the workpiece W, that is, the horizontal and vertical directions of each contact 26.27. It is set on an extension line in each direction at 45 degrees from the direction. The distance from the swing bottle 24 to the upper contact 26 and the distance from the lower contact 27 are substantially the same.

On the other hand, the distance 1i between the swing pin 24 and each connecting pin 20.22
The spacing between 1ti+ and 12 is configured to be inversely proportional to the diameter of the gear 9.10 attached to each of the aforementioned screw shafts 4.5. In other words, gear 9 diameter/gear 1o diameter = It 2
/j2 +. Therefore, the swing angle of the first arm 21 swinging around the swing bin 24 and the swing angle of the second arm 23 coincide with each other with high precision.

On the other hand, a spring member 28 as a biasing member is interposed between the first arm 21 and the second arm 23. As shown in FIG. 3, this spring member 28 is provided between the spring receiving member 2.1a of the first arm 21 and the spring receiving member 23a of the second arm 23, and the spacing between the arms 21.23 is maintained. It is biased in the direction of pushing and expanding. Therefore, there is no play between the arms, and variations in accuracy can be eliminated. Of course, the biasing direction may be reversed.

This rest device configured in this manner is capable of controlling each contact 26.
This will be dealt with by changing the position of 7. At this time, the upper screw shaft 4 rotates in a predetermined direction due to the rotation of the drive shaft 8, and the lower screw shaft 5 rotates in the opposite direction to rotate each sliding rod 18.19 via the operating screw portion 15.16. move in the opposite direction. As described above, the horizontal movement amount of the upper contact 26 and the vertical movement amount of the lower contact 27 are the same, and as shown in FIG.
．． The distance to the contact point 27 can always be kept constant.

Further, if the contacts 26 and 27 are worn out due to use, fine adjustment can be made using the fine adjustment members 11 and 12.

In addition, with this device, the displacement of the contact, which conventionally caused an error of about 0.1 mm, can be reduced to 0.1 μ or less.

(Effects of the Invention) As described above, the rest device of the present invention does not require readjustment such as replacing contacts or making fine adjustments during setup change such as model change, thereby improving work efficiency. Furthermore, by interposing the biasing member, backlash can be absorbed, allowing for highly accurate machining.

In addition, for component parts such as screw shafts, there is no need to provide reverse threads as in the past, which is not only advantageous in terms of manufacturing, but also
The mutual compatibility of parts is also increased, which is effective for maintenance and management of the equipment.

[Brief explanation of the drawing]

FIG. 1 is a partially broken side view of the rest device of the present invention;
FIG. 2 is an operational view of the tip arm portion, FIG. 3 is an enlarged view of the biasing member, and FIG. 4 is a side view of the conventional device. In the figure, 1 is a rest device, 2 is a grinding wheel, 4 is an upper screw shaft, 5 is a lower screw shaft, 18 is a first sliding rod, 19 is a second sliding rod, 21 is a first arm, 23 is the second arm, 24
is a swing pin, 26 is an upper contact, 2 is a lower contact, 5
1 is a grinding wheel, 52 is a rest device, 54 is a first sliding rod, 5
5 is a second sliding rod, 58 is a fulcrum, 69 is a stepping motor, P is a central axis, and W is a workpiece.

Claims (2)

[Claims] (1) A rest device for a grinding machine in which the positions of an upper contact that contacts the side of the workpiece and a lower contact that contacts the lower part can be changed relative to each other. a first arm that is swingable around a swing fulcrum, a second arm that includes the lower contact and is swingable around the swing fulcrum of the first arm, and from the upper contact to the swing fulcrum; A rest device for a grinding machine, characterized in that the distance is approximately the same as the distance from the lower contact to the swing fulcrum. (2) The rest device for a grinding machine according to claim 1, wherein a biasing member is interposed between the first arm and the second arm.