JPS6212241Y2 - - Google Patents

Description

[Detailed description of the invention] This invention is a linear micrometer in which the spindle held by the sleeve moves forward and backward in a straight line without rotating in the circumferential direction by moving the inner cylinder screwed into the sleeve forward and backward. It is related to.

Conventionally, as shown in FIG. 1, one end of an inner cylinder 2 is screwed into one end of a sleeve 1 so that it can move forward and backward, and a thimble 3 and an operating knob 4 are loosely fitted into the inner cylinder 2 on the outer periphery of the sleeve 1. are integrally fixed, the base end side of the spindle 5 is held in the other end of the sleeve 1 so as to be freely retractable, and the sleeve 1 and the spindle 5 are coupled with a key 6 and a keyway 7 so that they cannot rotate relative to each other, A linear micrometer has been considered in which the inner cylinder 2 is rotatably held between a stepped surface 5a provided at the base of a spindle 5 and a nut 8 screwed into the base. In the linear micrometer having this configuration, by rotating the operating knob 4, the spindle 5 moves forward and backward in the axial direction without rotating in the circumferential direction.

In such a micrometer, it is necessary to hold the inner cylinder 2 and the spindle 5 concentrically and without play in order to prevent a decrease in measurement accuracy. Therefore, it is desirable to fit the entire inner surface of the inner cylinder 2 to the outer periphery of the base of the spindle 5 without any gaps, but in this case, there is a drawback that the frictional resistance between the inner cylinder 2 and the spindle 5 increases. Moreover, in this case, the entire mating surface needs to be lap-finished with high precision, so machining of the inner cylinder 2 and spindle 5 requires skill.

In order to eliminate these drawbacks, conventionally, the first
As shown in the figure, support surfaces 9 and 10 are provided at two locations at the base of the spindle 5 at intervals, and these support surfaces 9 and 10 are brought into surface contact with the inner surface of the inner cylinder 2. In this case, in addition to providing the support surfaces 9 and 10 on the spindle 5, it is necessary to process the stepped surface 5a of the spindle 5 and the end surface of the nut 8.
In order to prevent the nut 8 from loosening, the nut 8' is added to create a double nut structure, which prevents the inner cylinder 2 from wobbling in the thrust direction (axial direction). Disadvantages: Adjustment to hold the spindle 5 requires skill; the mating parts of the support surfaces 9 and 10 and the inner surface of the inner cylinder 2 must be lap-finished with high precision; Processing is easier compared to the inner cylinder 2 and spindle 5.
Since the lap finish processing of the fitting part cannot be completely removed, there are disadvantages that this processing requires skill; and as a result of ..., the disadvantage that it takes a long time to assemble (connect) the inner cylinder 2 and the spindle 5. Ta.

The purpose of the present invention is to provide a linear micrometer that eliminates these drawbacks.By holding the inner cylinder with two tapers provided on the spindle, the inner cylinder can be moved in the thrust direction and with only these tapers. In addition to being supported in the radial direction, one of the two tapers is provided in a slotted nut screwed onto the spindle, thereby eliminating the need for lapping the peripheral surface of the base of the spindle. It is very small.

An embodiment of the present invention will be described below with reference to FIGS. 2 to 4. Incidentally, the same parts as those in FIG. 1 are given the same reference numerals, and the explanation thereof will be omitted.

In FIG. 2, a first taper 11 is formed at the intermediate portion on the base side of the spindle 5, and a tapered nut 12 is screwed into the end of the base so as to be movable forward and backward. 13 is a second taper provided on the nut 12 as a support member.

The tapers 11 and 13 are provided so that their diameters gradually increase as they move away from each other.
Moreover, the tapers 11 and 13 have the same degree of inclination. The inner cylinder 2 is supported at both ends by such tapers 11 and 13. In this way, the inner cylinder 2 is held concentrically with the spindle 5.

Further, the nut 12 is made of a metal material that has wear resistance and elasticity. This nut 12 is provided with slits 14 that are open on its inner and outer circumferential surfaces and at both ends, as shown in FIG. The slots 14 are actually formed at intervals of μ. Furthermore, the effective diameter of the female thread of the nut 12 is formed to be slightly smaller than the effective diameter of the male thread 5b at the base of the spindle 5 to which it is screwed.
The threads of the female thread 2 and the male thread 5b are pressed against each other. With this, Natsu 1
2 is frictionally fixed to the male screw 5b. Note that by screwing the nut 12 onto the male thread 5b, the slot 14 expands slightly and the taper 13 is slightly distorted;
Since the degree of expansion is set at μ intervals, the distortion of the taper 13 is almost non-existent, and as a result,
There is no problem in supporting the inner cylinder 2 concentrically with the spindle 5.

The thimble 3 is held between a taper 15 provided on the inner tube 2 and an operation knob 4 screwed onto the end of the inner tube 2. Moreover, FIG. 4 shows the relationship between the key 6 and the keyway 7 more clearly.

As explained above, in this invention, the inner cylinder is held on the spindle by the two tapers provided on the spindle, so that the inner cylinder can be supported without play in the thrust direction (axial direction) and radial direction with only these tapers. Can be done. As a result, it is no longer necessary to wrap the peripheral surface of the spindle base, which was required in the past, so it does not require skill to assemble the inner cylinder to the spindle without any looseness. and a cylinder can be quickly and easily joined with high precision.
Therefore, assembly time can be shortened without deteriorating accuracy, which is advantageous in manufacturing.

Also, one of the two tapers,
Since it is formed into a slotted nut that is screwed onto the spindle, the effective diameter of the female thread of this nut is made slightly smaller than the effective diameter of the male thread to which it is screwed, so that friction between the nut and the male thread is reduced. Can be fixed. This eliminates the need for a conventional double nut structure to prevent loosening, so no skill is required to adjust the inner cylinder to hold it on the spindle without any play in the thrust direction. Work can be done quickly.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a conventional linear micrometer. FIG. 2 is a sectional view of a linear micrometer showing an embodiment of the present invention. FIG. 3 is a perspective view of the nut shown in FIG. 2. FIG. 4 is a sectional view taken along the - line in FIG. 2. DESCRIPTION OF SYMBOLS 1... Sleeve, 2... Inner cylinder, 5... Spindle, 6... Key, 7... Keyway, 11... Taper (first), 12... Nut (support member), 13...
Taper (second), 14...slit.

Claims (1)

[Scope of utility model registration request] A spindle held in a sleeve so that it can move forward and backward in the axial direction of the sleeve and not be relatively rotatable, and an inner cylinder that is screwed into the sleeve so that it can move forward and backward in the sleeve can be relatively rotatably but not relatively displaceable in the axial direction. In the linear micrometer, the inner cylinder is connected between a first taper provided directly or indirectly on the spindle and a second taper of a support member attached to the spindle, with only these two tapers. Either one of the two tapers is provided on a slotted support member screwed onto the spindle so as to be supported without play in the thrust direction and the radial direction and to be held rotatably. Straight micrometer.