JPH02296050A - Cam fixing method to cam rotation axis - Google Patents

Abstract

PURPOSE:To fix a cam without dislocation in its fitting angle by providing a recessed part at the upper face of a rotation axis insertion hole of the cam, fitting an umbrella-shaped locating snap ring provided with cuts at its center hole and peripheral part into the recessed part and press-deforming the locating snap ring so as to be pressed to the rotation axis and the recessed part. CONSTITUTION:A rotation axis 5 is fitted into the rotation axis fitting hole 1a of a cam 1. A recessed part 2 is provided at the upper face of the cam 1 so as to fit a locating snap ring 4 therein. The locating snap ring 4 in the shape of an umbrella is provided with cuts 4b at its center hole 4' and cuts 4a at its peripheral part, and formed of elastic material such as plastics. The angular position of the cam 1 is decided by an adjusting bar 6 and the locating snap ring 4 is press-deformed. The diameter of the center hole of the locating snap ring is made approximately the same as that of the rotation axis, but the diameter of the peripheral part is made slightly smaller than that of the recessed part. The locating snap ring thus formed is brought into strong contact with the rotation axis and the peripheral wall of the recessed part at the time of its press-deformation. The cam fitting angle can be thus prevented from being dislocated so as to obtain rigid connection.

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to a method of fixing a cam to a cam rotation shaft.

"Prior Art" A microswitch or a photoelectric switch is used as a control element of an actuator using a motor as a drive source, and these control elements are operated using a cam.

That is, when the motor is energized, the output drive shaft rotates, and when the cam fixed to the output drive shaft rotates to a predetermined angle, it acts on the control element and stops power supply to the motor.

The cam has conventionally been fixed to the output drive shaft, that is, the cam rotation shaft, by screwing or by fitting the rotation shaft into a cam rotation shaft insertion hole provided in the cam. However, the fitting method is often unsuitable due to the need for angle adjustment, and the screwing method is often used. That is, if it is simply inserted, it will not shift even if the angle is adjusted (this is why most screws are used).

Furthermore, with this screw fastening method, adjustments are made in a temporary state, and after checking the results, the screws are further tightened and fixed, but there is a possibility that the screws may deviate from the adjustment point during final tightening.

Furthermore, especially when the material of the cam is resin, the dimensions of the cam itself often change due to temperature changes after it has been fixed by screwing, fitting, etc. In this case, the distance between the cam and the cam rotation shaft may change. There is a risk of loosening.

``Problem to be Solved by the Invention'' The present invention has been made in view of the above points, and it is possible to prevent the cam from shifting from the adjustment point when final tightening is performed when fixing by screwing. To provide a method for fixing a cam to a cam rotation shaft that maintains a strong connection between the cam and the cam rotation shaft even if the size of the resin cam changes due to temperature changes. It is.

"Means for Solving the Problems" The gist of the present invention is to provide a cam rotary shaft insertion hole and four circular parts with a desired diameter centered on the cam rotary shaft suction hole on the upper surface. The cam rotation shaft is inserted into the cam rotation shaft insertion hole of the cam, and then the cam is formed from an elastic material, and the outer circumference is cut out at appropriate intervals to form an umbrella shape, and an appropriate number of cuts of the required width are made in the center hole. The cam rotation shaft is passed through the center hole of a retaining ring whose center hole has a diameter that is approximately the same as the diameter of the cam rotation shaft, and whose outer diameter before pressurization is slightly smaller than the diameter of the recess in the cam. By shifting the retaining ring in the axial direction and deforming it by applying pressure from above within the recess of the cam, the center hole of the retaining ring is brought into pressure contact with the cam rotation shaft, and the outer circumference is brought into contact with the peripheral wall of the recess in the cam. The present invention provides a method for fixing a cam to a cam rotating shaft, thereby firmly connecting and fixing the cam to the cam rotating shaft.

"Example" Examples of the present invention will be described below.

In the figure, 1 is a cam having a cam rotation shaft insertion hole 1a,
A circular recess 2 having a desired diameter and having the cam rotation shaft fitting hole 1a as its center is provided on its upper surface.

Furthermore, the cam 1 has a cam rotation shaft fitting hole 1a from the side.
An adjustment rod insertion hole 3 is provided that reaches up to .

Reference numeral 4 denotes a retaining ring, which is pushed into the recess 2 of the cam l with the cam rotating shaft inserted through its center hole. The retaining ring 4 is made of an elastic material such as plastic having an appropriate hardness, and is shaped like an umbrella with an outer circumference of I.
! Notches 4a, 4a, . . . are formed at appropriate intervals, and an appropriate number of notches 4b, 4b, .

Further, the outer diameter of the retaining ring 4 in a state where it is not deformed by pressure is slightly smaller than the diameter of the recess 2 in the cam l (A in FIG. 2, top). Further, the diameter of the center hole 4' is approximately the same as the diameter of the cam rotation shaft.

Further, 5 is a cam rotation shaft, and 6 is an adjustment rod.

Thus, the cam rotation shaft 5 is inserted into the cam rotation shaft insertion hole 1a of the cam l.
Insert the m adjustment rod 6 into the adjustment rod insertion hole 3 of the cam l with the m adjusted rod inserted, and rotate the cam l to position it at an appropriate angle. After that, the cam rotation shaft 5 is passed through the center hole 4', and the retaining ring 4 is
to the recess 2 of the cam 1. When the retaining ring 4 is further pressed from above as indicated by the arrow in FIG. 5, the retaining ring 4 is deformed and its outer diameter increases, and its outer circumference comes into pressure contact with the peripheral wall of the recess 2 of the cam l. On the other hand, since the center hole 4' is in strong contact with the cam rotation shaft 5, the cam l is firmly connected and fixed to the cam rotation shaft 5 after all.

"Effect of the Invention J According to the present invention, in the case of screw fastening, if a retaining ring is used when temporarily tightening and adjusting the angle, it is possible to prevent the cam from shifting from the adjustment point when final tightening is performed. In addition, even if the dimensions of the resin cam change due to temperature changes and loosening occurs between the cam and the cam rotation shaft, the cam is firmly fixed to the cam rotation shaft by the elastic retaining ring. Therefore, the angle will not shift.Furthermore, it will be possible to adopt a fitting method that was previously postponed because it tends to shift even when the angle is adjusted. This makes it possible to perform the fixing work more quickly than when using screws.

[Brief explanation of drawings]

Fig. 1 is a plan view of the cam, Fig. 2 is a sectional view taken along line n-n in Fig. 3, Fig. 3 is a plan view of the retaining ring, and Fig. 4 is a sectional view taken along line n-n in Fig. 3.
Fig. 5 is a cross-sectional view of the main part in a state where the retaining ring in the recess of the cam is pressed and the cam is coupled and fixed to the cam rotation shaft. Cam la, recess 3, retaining ring 4' notch 4b, cam rotation shaft 6 cam rotation shaft insertion hole adjustment rod insertion hole center hole notch adjustment rod

Claims (1)

[Claims] The cam rotation shaft is inserted into the cam rotation shaft insertion hole of the cam, which has a cam rotation shaft insertion hole and a circular recess with a desired diameter centered on the cam rotation shaft insertion hole on the upper surface, and then the elastic It is formed from a material, has an umbrella shape, and has its outer periphery cut out at appropriate intervals, and the center hole is provided with an appropriate number of notches of the required width, and the diameter of the center hole is approximately the same as the diameter of the cam rotation shaft, and before pressurization. A retaining ring whose outer diameter is slightly smaller than the diameter of the concave portion of the cam is shifted in the axial direction by passing the cam rotation shaft through its center hole, and further deforming the retaining ring by applying pressure from above within the concave portion of the cam. By tightening the retaining ring, the center hole of the retaining ring is brought into pressure contact with the cam rotation shaft, and the outer circumference is brought into pressure contact with the peripheral wall of the recess in the cam, thereby firmly connecting and fixing the cam to the cam rotation shaft. How to fix the cam.