JPH0329618Y2 - - Google Patents

Description

[Detailed description of the invention] (Industrial application field) The invention consists of two hollow shafts with one end closed and the other end open, with the open ends of these hollow shafts facing each other in the axial direction. an inner hollow shaft and an outer hollow shaft that are slidably and non-rotatably interfitted with each other;
a compression spring disposed in the inner space of the hollow shafts, a flange projecting radially outward at the open end of the inner hollow shaft, and a limit on the outer hollow shaft engaging the flange; This invention relates to a telescopic joint provided with a holding portion.

(Prior Art) This type of telescoping shaft joint is used, for example, in an electric shaver to drive the drive gear between the drive gear of the electric motor and the rotary cutter. There are some that are listed in the publication.

This publication proposes what is shown in FIG. In this shaft joint, a drive gear (not shown) of an electric motor is meshed with a gear provided on an outer hollow shaft 100, an inner hollow shaft 101 is connected to a rotary cutter 102, and the inner hollow shaft 101 is connected to a rotary cutter 102, which is provided at the open end of the inner hollow shaft. An upright wall 103 that protrudes radially inward from the inner wall of the outer hollow shaft 100 is fitted into the recess between the flanges 101a that protrude radially outward, making it movable in the axial direction and non-rotatable relative to each other, and the spring 104 At the same time, the inner hollow shaft 101 is pressed upward, and the flange 101a of the inner hollow shaft 101 is brought into contact with the hook-shaped holding part 105 provided at the top of the outer hollow shaft 100 and protrudes inward in the radial direction, and moved upward. limit. An axially extending slit 106 is provided in the outer hollow shaft 100 on either side of each retaining portion 105 to allow the retaining portions 105 to flex outwardly to facilitate disassembly and assembly of the hollow shafts.

With this configuration, the inner hollow shaft 101 and the rotary cutter 102 connected to the inner hollow shaft are able to expand and contract in the axial direction with respect to the outer hollow shaft 100, and are also slightly tiltable.

(Problem to be solved by the invention) However, in conventional shaft joints, an upright wall is provided on the inner wall of the outer hollow shaft, and a hook-shaped holding part is provided on the top of the outer hollow shaft, and the The mold has a complicated shape because slits must be formed in the mold, and the cost of the mold increases when molded with plastic.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a telescoping shaft joint that is simple in construction and easy to assemble.

Furthermore, in the case of the conventional shaft joint as described above, the range of tilting is small, and it cannot be applied to a shaving device in which the shaving head is tiltably supported with respect to the shaving device body.

Therefore, another object of the present invention is to provide a telescoping shaft joint which has a wide tilting range and can be applied to a shaving machine with a tiltable shaving head.

(Means for Solving the Problems) In order to achieve the above-mentioned first objective, the telescopic shaft joint of the present invention has a circular cross section that allows the inner hollow shaft and the outer hollow shaft to be slidably fitted into each other. , a plurality of flexible fingers arranged circumferentially through slits are provided on the open end side of the inner hollow shaft, the flanges are provided on the edges of the fingers spaced apart from each other at equal intervals, and the outer hollow shaft It is characterized by providing guide slots extending in the axial direction from the closed bottom surface of the finger and slidably accommodating the flanges of the fingers.

In order to achieve the above-mentioned second object, in a preferred embodiment of the present invention, the upper part of the outer hollow shaft is shaped like a truncated cone which expands upwardly.

(Function) According to the configuration of the present invention, the fingers at the end of the inner hollow shaft are bent inward and inserted into the outer hollow shaft, and the flange provided on the fingers is inserted into the guide groove in the lower part of the outer hollow shaft. Both hollow shafts can be combined by fitting them together. Further, the inner hollow shaft is guided in the axial direction along the side edges of each guide slot, and the stroke movement is limited by the upper and lower edges of the guide slot.

According to the configuration of the preferred embodiment described above, in a shaving device in which the shaving head is tiltably supported with respect to the shaving device main body, a wide range of tilting movement is possible that can sufficiently accommodate the maximum tilting movement of the shaving head.

(Embodiment) Next, a preferred embodiment of the telescopic shaft joint according to the present invention will be described with reference to the drawings.

The telescoping shaft joint 1 according to the present invention is composed of an inner hollow shaft 2 and an outer hollow shaft 3 each having a circular cross section with one end open. The inner hollow shaft 2 is provided with a slit 4 extending upward in the axial direction from the lower end edge of the open end, and three fingers 5 are arranged at equal intervals in the circumferential direction. A flange 6 is provided that projects outward.

In the illustrated embodiment, the upper portion 3a on the open end side of the outer hollow shaft 3 is formed into a truncated conical shape that expands upward, and extends upward in the axial direction from the closed bottom surface to form the flange 6 of the finger 5. Three guide groove holes 7 are provided, each of which is slidably accommodated therein.

Spring supports 8 and 9 are provided inside the inner hollow shaft and the outer hollow shaft, respectively, so that each end of a coiled compression spring 10 can be supported.

To assemble both hollow shafts, as shown in FIG. It can be easily assembled by inserting it, releasing the pressing force on the finger 5, and fitting the flange 6 into the guide groove hole 7. The inner hollow shaft 2 is provided with a spindle 11 and a bush 12 that project upward. Further, a gear 13 is integrally formed on the outer hollow shaft 3. In the illustrated embodiment, the gear 13 is provided at the upper edge of the outer hollow shaft 3, but it may also be provided at another portion, for example at the bottom edge.

FIG. 4 shows a partially sectional view of a shaving device having a preferred embodiment of the invention shown in FIG. 1 and having a tiltable shaving head.

This shaving device supports a shaving head 22 tiltably in all directions via a cardan suspension mechanism on a top plate 21 of a housing 20 containing a drive mechanism. The Cardan suspension mechanism consists of a pair of diametrically aligned pivots 2 provided on the top plate 21.
3, a support ring 24 is rotatably attached to the support ring 24, and a support plate 26 is rotatably provided around a support shaft 25 provided on the support ring 24 so as to be perpendicular to the axes of the pivot portions 23. A rubber waterproof cover 2 is placed around this cardan suspension mechanism.
7, and above this is a shaving head 22.
Install. Support ring 24 of cardan suspension mechanism
Inside is a telescopic shaft joint according to the present invention (see Figure 1).
Place. A spindle cap 28 is attached to the spindle 11 of the inner hollow shaft 2 that penetrates upward from the shaft sealing part of the waterproof cover 27, and this spindle cap 28 is engaged with a rotating inner cutter (not shown), and is connected to the fixed outer cutter 29. Allow relative rotation.

The outer hollow shaft 3 of the telescopic joint is rotatably supported by the top plate 21, and a gear 13 of the outer hollow shaft is meshed with a gear (not shown) connected to the drive shaft of the electric motor.

According to the illustrated embodiment, the upper part of the outer hollow shaft 3 has a truncated conical shape that widens upward, so that it can also accommodate the maximum tilting of the shaving head of the shaving device shown in FIG. can.

What has been described above is merely an example of the present invention, and it goes without saying that various changes can be made within the scope of the claims. It can also be used for telescoping shaft joints other than shaving devices. for example,
When this invention is used in the shaft coupling between the motor and reel spindle of a portable cassette tape recorder,
Since external vibrations are absorbed by the aforementioned elasticity and tiltability of the shaft joint, the tape can run smoothly.

(Effects of the invention) As described above, according to the invention, a telescoping shaft joint can be easily disassembled and assembled by simply providing a slit in the inner hollow shaft and a guide groove in the outer hollow shaft. is obtained.

Furthermore, since the telescopic shaft joint of the present invention has a truncated conical shape at the upper part of the outer hollow shaft, the tilting range is large. You can get it.

[Brief explanation of drawings]

FIG. 1 is a partial sectional view of a preferred embodiment of the telescoping joint according to the invention in a fully tilted state, and FIGS. 2a and b are side views of the inner hollow shaft of the shaft joint of FIG. 1, respectively. 3a, b and c are respectively a plan view, a side view and a bottom view of the outer hollow shaft of the shaft coupling of FIG. 1, and FIGS. 4a and b are respectively of the shaft coupling of FIG. FIG. 5a is a partial cross-sectional view of a shaving device in which a shaving head incorporating a tiltable shaving head is shown in different cross-sections.
FIG. 5b, an explanatory diagram of a conventional telescoping shaft joint, is a sectional view taken from above the - line in FIG. 5a. 1... Telescopic shaft joint, 2... Inner hollow shaft, 3
...Outer hollow shaft, 4...Slit, 5...Finger, 6...Flange, 7...Guide slot, 8, 9...
... Spring support part, 10 ... Coil spring, 11 ... Spindle, 12 ... Bush, 13 ... Gear, 2
0...Housing, 21...Top plate, 22
...Shaving head, 23... Axis part, 24...
Support ring, 25...Support shaft, 26...Support plate, 27...Waterproof cover, 28...Spindle cap, 29...Fixed outer blade.

Claims (1)

[Scope of utility model registration request] Two hollow shafts with one end closed and the other end open, the open ends of these hollow shafts facing each other, and an inner hollow shaft fitted into each other so as to be slidable in the axial direction and non-rotatable relative to each other; outer hollow shafts and a compression spring disposed in the inner space of the hollow shafts; the open end of the inner hollow shafts is provided with a radially outwardly projecting flange; In a telescopic joint provided with a limiting holding part that engages with a flange, the inner hollow shaft and the outer hollow shaft have a circular cross section that allows the inner hollow shaft and the outer hollow shaft to be directly inserted into each other, and the upper part of the outer hollow shaft is directed upward. The inner hollow shaft has an expanding truncated conical shape, and further includes a plurality of flexible fingers arranged in the circumferential direction through slits on the open end side of the inner hollow shaft,
The flanges are provided at the edges of the fingers spaced apart from each other at equal intervals, and guide groove holes are provided that extend in the axial direction from the closed bottom surface of the outer hollow shaft and slidably accommodate the flanges of the fingers. Telescoping shaft joint.