JPH0620085Y2 - Limit plug gauge for screws - Google Patents

Description

TECHNICAL FIELD The present invention relates to a thread limit plug gauge for inspecting an internal thread, and more particularly, to an improvement of a composite gauge that integrally includes a through gauge portion and a dead gauge portion. It is a thing.

2. Description of the Related Art When performing accuracy measurement or shape inspection of internal threads, a pair of gauges and stop gauges formed corresponding to the lower and upper limits of the allowable accuracy range of internal threads are used to check whether or not they are within the appropriate range. Limit plug gauges for screws to be inspected are used. For example, the plug gauge 50 shown in FIG.
Then, the passage gauge portion 52 and the stop gauge portion 54 are provided at both ends of the handle portion 56, and with respect to the female thread to be inspected which can be screwed into the passage gauge portion 52 without difficulty,
When the dead gauge portion 54 stops within the specified number of screwing-in times, it is determined that the female thread to be inspected is within its allowable accuracy range.

The plug gauge 60 shown in FIG. 5 has a through gauge 62 and a stop gauge 6 on the side opposite to the handle 66.
4 are axially spaced a predetermined distance and are positioned so that the helical thread windings are aligned with one another. According to this plug gauge 60, since it can be suitably mounted on a torque-controlled electric screwdriver or the like, the passing side and the stop side can be continuously inspected by one screwing operation, and the inspection work can be performed efficiently. Can be done.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention In the plug gauge 60, when the stop gauge portion 64 is screwed into the female thread to be inspected, the passing gauge portion 62 may not yet pass through the female thread to be inspected. In such a case, for example, as shown in FIG. 6, if the inspected female screw 40 has a cumulative pitch error,
Even if the female thread 40 to be inspected, which originally does not stop within the specified number of times of screwing of the stop gauge portion 64, the rotation of the plug gauge 60 is restricted, so that it can stop within the specified number of times of screwing and be judged as a pass. There is a possibility that the inspection accuracy by the stop gauge portion 64 cannot be sufficiently obtained.

On the other hand, like the plug gauge 70 shown in FIG. 7, if the distance between the passage gauge portion 72 and the stop gauge portion 74 is configured to be larger than the length of the female screw 40 to be inspected, the stop gauge by the passage gauge portion 72 will be described. Although it is possible to avoid the influence on the portion 74, in this case, the stop gauge portion 7 after the passage gauge portion 72 comes off the female screw 40 to be inspected
4 when screwing in, or as shown in FIG.
It is not easy to adjust the screw threads when pulling back 2
Especially in the inspection work using an electric screwdriver or the like, there is a possibility that the inspected female screw 40 or the plug gauge 70 may be damaged.
There was an inconvenience that the work could not be performed smoothly.

The present invention was made in the background of the above circumstances,
It is an object of the invention to provide a limit plug gauge for a screw which enables efficient inspection work with high inspection accuracy.

Means for Solving the Problems In order to achieve the above object, the gist of the present invention is that the gauge portion and the dead gauge portion are concentrically integrated with each other with a predetermined interval in the axial direction. (A) a guide means for guiding one of the gauge portion and the dead gauge portion so as not to be rotatable about the axis and movable in the axial direction with respect to the other; b) Position one of the gauge portion and the dead gauge portion as described above so that the helical thread of the screw thread is aligned with the other, and allow a slight change in the axial distance between the one and the other. And an elastic member.

In the above-described thread limit plug gauge, one of the passing gauge portion and the dead gauge portion is guided by the guide means so as not to be rotatable about the axis and movable in the axial direction, and Since the helical thread of the screw thread is positioned with respect to the other by the elastic member, at the time when the inspection of the passing side is completed, the passing gauge part that is screwed into the female thread first is The stop gauge portion is guided and bites into the internal thread without adjusting the thread, and the stop side inspection is quickly and continuously performed following the street side inspection. On the other hand, since the elastic member allows a slight change in the axial distance of one of the passing gauge portion and the dead gauge portion to the other due to the deformation of itself, the female thread to be inspected is screwed at the same time as the passing gauge portion and the dead gauge portion. Even when they are fitted together, the dead gauge part does not pass through and is not constrained by the dead gauge part due to the accumulated pitch error of the internal thread, etc., and the dead gauge part is inspected with sufficient accuracy. .

As a result, a series of internal thread inspection by the passing gauge portion and the dead gauge portion can be easily and quickly performed with high accuracy. In particular, when the screw limit plug gauge of the present invention is mounted on an electric screwdriver and an internal thread inspection is performed at high speed, the inspection work can be performed extremely smoothly.

Embodiment Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 2 shows a limit plug gauge for screws (hereinafter,
FIG. 1 is a front view of a plug gauge 10), and FIG.
FIG. 4 is a partial cross-sectional view showing in detail a partial cutout of a main part thereof. The plug gauge 10 has a tip guide portion 18, a through gauge portion 12, a dead gauge portion 14, in order from the tip thereof.
The handle portion 16 is concentrically and integrally provided.

As can be seen from FIG. 1, a stop gauge portion 14 provided with a stop side thread gauge and a handle portion 1 having a hexagonal chamfer.
6 and 6 are formed integrally with the main body 17. Further, inside the main body 17, an insertion hole 24 having an opening on the blind gauge portion 14 side is concentrically formed, and a shaft 26 having the tip guide portion 18 at one end is provided in the insertion hole 24. The shaft is fitted. A rotation stopping surface 28 is provided on the tip end side portion of the shaft 26 fitted into the insertion hole 24, while a set screw 30 is screwed from the outer peripheral side of the insertion hole 24 toward the axial center. The shaft 26 is fixed to the main body 17 by tightening the anti-rotation surface 28 with the set screw 30. On the other hand, the passing gauge portion 12 is composed of a cylindrical gauge member 13 having a passing side thread gauge formed on the outer periphery thereof. The gauge member 13 is slidable on the shaft 26 with the elastic sleeve 20 a interposed between the gauge member 13 and the end guide portion 18, and the elastic sleeve 20 b and the adjustment spacer 22 interposed between the gauge member 13 and the dead end gauge portion 14. Is fitted to.

The thread shape of the passing side thread gauge in the passing gauge portion 12 is finished to the minimum dimension of the regular dimension of the female thread to be inspected plus the lower limit of the fitting tolerance, that is, the minimum critical dimension of the female thread to be allowed. On the other hand, in the stop side thread gauge in the stop gauge portion 14, the maximum dimension obtained by adding the upper limit of the fitting tolerance to the regular dimension of the female thread to be inspected, that is, the maximum allowable dimension of the female thread is stipulated from the tip. The shape of the screw thread located at the number of turns (for example, two turns) is finished.

On the outer peripheral surface of the shaft 26 and the outer peripheral surface of the gauge member 13 at the fitting portion of the shaft 26 and the gauge member 13, the outer guide groove 34 and the inner guide groove 36 are parallel to the axial center at three positions equidistant in the circumferential direction. In the outer guide groove 34 and the inner guide groove 36, a plurality of guide balls 38 for torque transmission are rollably arranged. These outer guide groove 34 and inner guide groove 3
6 and the guide mechanism 32 including the guide ball 38 constitutes the guide means in the present embodiment, the passing gauge portion 12 is supported by the stop gauge portion 14 so as not to be rotatable about the axis, and is moved in the axial direction. It is possible to be guided.

However, the elastic sleeve 20a, the gauge member 13, the elastic sleeve 20b, and the adjusting spacer 22 are inserted without a gap between the tip guide portion 18 and the dead gauge portion 14, and the through gauge portion 12 and the dead gauge portion are inserted. The portion 14 is separated from the portion 14 at a predetermined distance in the axial direction, and is positioned such that the helical windings (lead wires) of the screw threads are aligned with each other.

The elastic sleeves 20a and 20b closely intervened on both sides of the gauge member 13 are formed of an elastic material such as rubber in a ring shape so that they can be deformed by receiving a compressive force in the axial direction. And is pre-compressed so as to have a predetermined axial length in the assembled state. Therefore, when the passage gauge portion 12 is slightly moved leftward or rightward in FIG. 1 with respect to the stop gauge portion 14, either one of the elastic sleeves 20a and 20b is compressed and deformed, and the other is compressed. It is stretched and deformed to allow an increase or decrease in the axial distance between the passing gauge portion 12 and the dead gauge portion 14. Therefore, in this embodiment, the elastic sleeve 20 is
a and 20b stop the passage gauge portion 12 and the gauge portion 1
The coil windings of the screw thread are positioned so as to coincide with each other with respect to 4, and also function as an elastic member that allows a slight change in the axial distance of the passing gauge portion 12 with respect to the stop gauge portion 14.

The adjustment spacer 22 is a cylindrical member made of metal, hard synthetic resin, or the like, and the through-gauge portion 12 and the dead-gauge portion 14 correspond to the axial length of the female screw to be inspected. The distance between them is adjusted so that they are screwed together at the same time. The adjustment spacer 22 can be easily replaced with another one having a different length by loosening the set screw 30 and removing the shaft 26 from the main body 17.

Next, a procedure for inspecting an internal thread using the plug gauge 10 configured as described above will be described below.

First, the adjustment spacer 22 is selected in advance according to the axial length of the inspected female screw 40 to assemble the plug gauge 10. Then, the handle portion 16 is gripped by an electric driver (not shown), the plug gauge 10 is set, and the torque limiter of the electric driver is adjusted to set the drive torque to a predetermined inspection torque.

Next, the axial center is aligned with the opening of the female screw 40 to be inspected, the tip guide portion 18 is applied, and the electric screwdriver is driven at a low speed to perform thread alignment. When the passing gauge portion 12 bites the female screw 40 to be inspected, the high speed rotation is switched to and the passing gauge portion 12 inspects the passing side.

If the gauge portion 12 passes without difficulty and passes, the plug gauge 10 is continuously rotated as it is, and the stop gauge portion 14 is screwed into the inspected female screw 40 to inspect the stop side. Then, when the screwing of the plug gauge 10 is stopped, the driving of the electric screwdriver is stopped. At this time, the inspected female screw 40 passes through the gauge portion 12 and the stop gauge portion 14.
When the internal thread 40 to be inspected has a cumulative pitch error, the passing gauge portion 12 tries to be slightly moved in the axial direction with respect to the stop gauge portion 14 when the female thread 40 to be inspected has a cumulative pitch error. In such a case, the elastic sleeves 20a and 20b are compressed and expanded and deformed.
As shown in FIG.
It is possible to inspect the stop side with sufficient accuracy without being affected by. At this time, the pass / fail judgment is made based on whether or not the plug gauge 10 has stopped within the prescribed number of screw-ins (the number of threads) from the tip.

After the inspection of the stop side is completed, the electric driver is driven in reverse rotation at high speed. At this time, even if the passing gauge portion 12 is in a state of being passed through the female screw 40 to be inspected (which may occur when the passing side fails, the passing gauge portion 12).
Since the respective helical windings of the plug gauge 10 and the stop gauge portion 14 coincide with each other, the plug gauge 10 can be pulled out at once without the need to adjust the thread of the passage gauge portion 12.

As described above, according to the plug gauge 10 of the present embodiment, the dead gauge portion 12 and the dead gauge portion 14 simultaneously fit into the female screw 40 to be inspected when the spiral windings are matched with each other. The inspection of the stop side by means of 14 can be performed continuously and quickly and easily following the inspection of the stop side, and the elastic sleeves 20a and 20b allow a slight change in the axial distance of the stop gauge part 12 to the stop gauge part 14. Since it is allowed, even when the passing gauge portion 12 and the stop gauge portion 14 are simultaneously screwed into the female screw 40 to be inspected, the conventional plug gauge in which the passing gauge portion and the stop gauge portion are completely fixed As described above, the stop gauge does not pass through and is not constrained by the gauge due to the accumulated pitch error of the inspected female screw 40, and the stop side inspection accuracy is good. Than it is maintained.

Further, according to the plug gauge 10 of the present embodiment, since the adjusting spacer 22 is selected and used according to the axial length of the female screw 40 to be inspected, the spacer 22 for adjustment is individually selected according to the length of the female screw 40 to be inspected. It is not necessary to manufacture a plug gauge, and one plug gauge 10 can be inspected for all the female threads to be inspected having a length within the adjustable range adjustable by the adjustment spacer 22.

Further, since the plug gauge 10 of this embodiment can be easily disassembled, it is possible to replace and use only the passage gauge portion 12 that easily reaches the wear limit relatively early, and the passage gauge portion 12 and the stop gauge can be used. There is an advantage that the cost is reduced as compared with the conventional one in which the gauge portion 14 is integrally formed.

Although one embodiment of the present invention has been described in detail above, the present invention can be implemented in other modes.

For example, in the above-described embodiment, the elastic sleeves 20a and 20b made of an elastic material such as rubber are used as the elastic members.
However, instead of these, a resin sleeve made of a soft synthetic resin having elasticity, a compression coil spring, etc. may be provided, respectively, and a single elastic material capable of compressive deformation and tensile deformation is used. The member may be arranged on one side of the gauge member 13.

Further, in the above-described embodiment, the elastic sleeves 20a and 20b are inserted in a pre-compressed state, but the positioning function of the gauge member 13 can be obtained even if it is not pre-compressed.

Further, in the above-described embodiment, the guide balls 38 are arranged in the outer guide groove 34 and the inner guide groove 36 as guide means, but instead of this, a sliding key having good slidability is provided on the shaft 26. It is possible to use other guide means such as arranging on the outer peripheral surface of the above and providing a corresponding key groove in the gauge member 13.

Further, in the above-described embodiment, the tip guide portion 18 is formed integrally with the shaft 26, the shaft 26 and the main body 17 are integrally fixed by the set screw 30, and the gauge portion 12 is passed through them. Although the gauge member 13 is guided so as to be movable in the axial direction, for example, the passage gauge portion 12 is integrally formed with the shaft 26 together with the tip guide portion 18, and the stop gauge portion 14 is formed on the passage gauge portion 12 or the like. Alternatively, the guide may be movably provided.

Further, in the above-described embodiment, the stop gauge portion 14 and the handle portion 16 are integrally formed in the main body 17, and the main body 17 and the shaft 26 are separately configured. 17 is integrally formed, the stop gauge portion 14 and the tip guide portion 18 are separated from the main body 17 and the shaft 26, and the stop gauge portion 14 and the tip guide portion 18 are fixed to the shaft 26 by a set screw or the like. It may be configured as follows.

Further, in the above-described embodiment, the adjusting spacer 22 for adjusting the distance between the passing gauge portion 12 and the dead gauge portion 14 is provided, but such an adjusting means is not provided, The portion corresponding to the adjusting spacer 22 is the main body 17
The effect of the present invention can be obtained even if it is formed integrally with Alternatively, instead of the adjusting spacer 22, for example, a plurality of blind holes (center holes) are formed on the surface of the rotation stop surface 28 of the shaft 26 at intervals equal to the pitch of the screw thread, and the set screws 30 are provided in the blind holes. You may comprise so that it may fit. When such a positioning means is provided, the elastic sleeve 20b is attached to the gauge member 1
3 is provided with a snap ring or the like for positioning the shaft 26 in a state of being in close contact with the elastic sleeve 20b and the main body 1.
A space may be formed between the space and 7.

Further, in the above-described embodiment, the plug gauge 10 is rotationally driven by using the electric driver, but it is needless to say that the same effect can be obtained even when the inspection is performed by the manual operation of the operator. That is.

It should be noted that the above description is merely one embodiment of the present invention, and the present invention can be implemented with various modifications and improvements based on the knowledge of those skilled in the art without departing from the spirit thereof.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view showing in detail a main part structure of a limit plug gauge for a screw according to an embodiment of the present invention. FIG. 2 is a front view showing the entire thread limit plug gauge of FIG. FIG. 3 is a diagram for explaining a state of inspecting a female screw by the screw limit plug gauge of FIG. Figure 4,
5 and 7 are views corresponding to FIG. 2 showing a conventional limit plug gauge for screws. FIGS. 6 and 8 are diagrams corresponding to FIG. 3 in the conventional example of FIGS. 5 and 7, respectively. 10: Limit plug gauge for screw 12: Through gauge portion 14: Stop gauge portion 20a, 20b: Elastic sleeve (elastic member) 32: Guide mechanism (guide means)

Claims (1)

[Scope of utility model registration request] 1. A screw limit plug gauge integrally provided with a concentric passage gauge portion and a stop gauge portion at a predetermined interval in the axial direction, wherein the gauge portion and the stop gauge are provided. Guide means for guiding one of the gauge portions so as not to be rotatable about the axis and movable in the axial direction with respect to the other, and one of the above-mentioned gauge portion and the dead gauge portion, and a helical thread winding with respect to the other. And an elastic member which allows the slight variation of the axial distance with respect to the other of the one and the other, and the limit plug gauge for a screw.