JPH1137173A - Bidirectional transmission dog clutch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce noise by providing an engaging part formed of one protruding part and two recessed parts to be fitted thereto, between a crest part end face and a root part end face relative to each other, and fitting one recessed part to the protruding part at the time of transmitting driving force in either normal or reverse direction. SOLUTION: One protruding part 43 protruded to the opposed flange side, and two recessed parts 44, 46 to be fitted thereto are formed at an end face 36a of a crest part 36 and a bottom face 37a of a root part 37 relative to each other at the time of transmitting driving force. The positions of the recessed parts 44 are set in relation to the protruding part 43 so that the protruding part 43 is fitted to the recessed part 46 at the time of normal rotating transmission and that the protruding part 43 is fitted to the recessed part 44 at the time of reverse rotating transmission, thus forming an engaging part 47 for positioning the crest part 36 to the root part 37. Positioning of the crest part 36 and root part 36 in an opposite direction to a torque applied direction is therefore performed in either case of transmitting rotation in normal or reverse rotating direction, so that the engaging play of a dog clutch is reduced, and noise is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a two-way transmission dog clutch for transmitting rotation in two directions between two shafts.

[0002]

2. Description of the Related Art Conventionally, as shown in FIGS. 7 and 8, a flange c having concave and convex ridges a and valleys b meshing with each other,
A dog clutch is known which transmits the rotational driving force of one shaft to the other shaft by fitting the shafts d to the ends of both shafts and meshing the ridges a and the valleys b as necessary. Has been used, for example, in a tractor for transmitting a driving force to a work machine (rotary) of a hitch mechanism. And the dog clutch used for the above hitch mechanism,
Since it is necessary to rotate the rotary forward or reverse, P
It is configured such that the rotational driving force of the TO shaft in both the forward and reverse directions can be transmitted to the work implement.

[0003]

At this time, when the dog clutch is normally rotated (rotated in the X direction), the peak portion a is fitted to the step b1 on the deep side of the valley portion b formed in two steps. ｛Figure 8
(B) が Although the transmission efficiency is relatively high and the noise is small, the outer step b2 is used during reverse rotation (when rotating in the Y direction).
8 (c)}, the peaks a and the valleys b abut in the transmission direction, but the peaks a and the valleys b do not abut in the opposite direction. a and the valley b are fitted with a relatively large backlash, and there is a drawback that the backlash generates noise.

[0004]

SUMMARY OF THE INVENTION In order to solve the above problems, a two-way transmission dog clutch according to the present invention has two shafts.
Flanges 18,3 mounted on opposite ends of 6,28
1 and opposite end faces 18 of the flanges 18, 31
a and 31a are provided with an uneven peak portion 36 and a valley portion 37 that mesh with each other to transmit rotation in both forward and reverse directions, and the end surface 36a of the peak portion 36 and the bottom surface 37a of the valley portion 37 are pressed against each other. As described above, in the dog clutch 34 in which the flanges 18 and 31 are urged in the axial direction, the opposed flanges 31 and 31 are located between the end surface 36a of the peak portion 36 and the bottom surface 37a of the valley portion 37 that face each other when the driving force is transmitted. One protruding portion 43 protruding to the 18th side and two concave portions 44 and 4 fitted into the protruding portion 43
6 is provided, and the engaging portion 47 is arranged so that one of the concave portions 44, 46 and the convex portion 43 are fitted to each other when driving force is transmitted in both forward and reverse directions. Features.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a left side view showing an auto hitch 2 portion provided at a rear portion of a body 1 of a tractor, to which a working machine 5 for tilling can be automatically connected and mounted.
1 shows a front view of an essential part of the auto hitch 2, and the auto hitch 2 has an inverted U-shaped hitch frame 3 made of a pipe material as in the prior art as shown in FIGS. An upper hook 4 fixed at a central position and a lower hook 6 fixed at lower left and right ends are provided. The work machine 5 is provided with a rotary 5a for tilling, and the rotary 5a is driven to rotate in both forward and reverse directions to perform tilling on a field or the like.

At this time, a hook plate 7 is rotatably supported on the side surfaces of the left and right lower hooks 6,
An operation lever 8 is supported by a guide hole 10 formed in the upper hook 4 and having a substantially L shape in a side view. The operation lever 8 and the hook plate 7 are connected by an arm 9, and the hook plate 7 Is urged in the direction to close the lower hook 6, so that the operation lever 8 is
Is constantly biased toward the bent portion side to control the operation of the hook plate 7. On the other hand, the lower left and right ends of the hitch frame 3 are connected by a connecting frame 11 made of a pipe material, and a PTO connection output section 13 is supported via a yoke bracket 12 at a substantially center of the connecting frame 11 in a front view.

The PTO connection output section 13 is connected via a yoke joint 14 to a PTO shaft 20 protruding from the transmission case 15 side of the body 1, and power from the PTO shaft 20 is transmitted. And upper hook 4
Are connected to a bracket 24 provided on the upper rear end side of the fuselage 1 via a top link 25, and both ends of the hitch frame 3 are connected via lower left and right links 30 whose front ends are pivotally fixed to the fuselage 1 side. The automatic hitch 2 is formed by being connected to the side. At this time, the auto hitch 2 is freely movable up and down.

[0008] Thus, from the state where the machine body 1 and the work machine 5 are separated from each other, the work machine 5 is erected on the ground, the body 1 is retracted with the auto hitch 2 lowered, and the upper hook 4 is moved to the work machine 5. Pin 5 connected to upper hook 4 provided on the side
By lifting the auto hitch 2 to lift the upper hook 4 and lifting the pin 5c by the upper hook 4, the pin 5d automatically connected to the lower hook 6 provided on the working machine 5 side enters the lower hook 6. After the hook plate 7 closes the lower hook 6 and the pin is held,
The holding of the pin 5d is locked by the operation lever 8 and the guide hole 10, and the working machine 5 is automatically set to the machine body 1 with one touch.

On the other hand, the PTO connection output section 13
(The PTO connection output section 13 has a cross section taken along the line AA in FIG. 2.) As shown in FIG. 2, a hollow output shaft 16 connected to the PTO shaft 20 via the above-described yoke joint 14;
A flange 18 is externally fitted to the end of the output shaft 16 via a key 17, a holder 21 for rotatably supporting the flange 18 via a bearing 19, and a buffer 22 on the holder 21. Cap 2 attached via
3 and the like, and one end surface of the flange 18 protrudes rearward from the yoke bracket 12.

On the work machine 5 side, when the work machine 5 is attached by the above-described auto hitch 2, the PTO connection output section 13 is connected.
A transmission unit 26 is provided which is automatically connected to the work machine 5 and which transmits the driving force to the work machine 5. As shown in FIG.
Reference numeral 6 denotes an adapter 27 which is removably fitted to the output shaft 16.
, A holder 29 integrally fitted on the drive shaft 28, and a flange 3 slidably fitted in the axial direction so as to rotate integrally with the holder 29.
A spring 32 for elastically urging the flange 31 toward the adapter 27 of the drive shaft 28;
And a cover 33 for covering the outer periphery of the cover 2.

When the work machine 5 is mounted by the automatic hitch 2, the end face 18a of the flange 18 projecting rearward from the yoke bracket 12 and the end face 31a of the adapter 27 on the flange 31 face each other, and the output shaft 16 The adapter 29 of the drive shaft 28 is inserted into the hollow portion of the flange.
The upper and lower flanges a and 31a are formed with concave and convex ridges 36 and valleys 37 which mesh with each other to transmit rotation in both the forward and reverse directions. , 31 from the output shaft 16 to the drive shaft 28.

When the ridges 36 and the valleys 37 are engaged with each other, the spring 32 causes the flange 31 to move the flange 18.
The end face 36a of the peak portion 36 formed on the flange 18 and the valley portion 37 formed on the flange 31
Are pressed against each other (see FIG. 6). That is, when the work machine 5 is mounted, the output shaft 16 and the drive shaft 28 are automatically removably connected via the dog clutch 34 constituted by the flanges 18 and 31 and transmitting rotation in both forward and reverse directions.

Next, the structure of the peak portion 36 and the valley portion 37 of the dog clutch 34 will be described in detail. As shown in FIG. 4 (a rear view of the flange 18), the ridge 36 is formed on an end surface 18a of the flange 18 (an end surface facing the flange 31).
Is protruded in a convex shape so as to extend a predetermined length in the circumferential direction,
A plurality of tapered surfaces 3 are provided at predetermined intervals, and two radial surfaces on the peripheral surface of each peak portion 36 perform rotation transmission in the forward rotation direction X for rotating the work machine 5 (rotary 5a) in the forward direction.
8 and a reverse rotation direction Y for rotating the rotary 5a in the reverse direction.
And a tapered surface 39 that transmits the rotation of the motor.

On the other hand, as shown in FIG. 5 (a front view of the flange 31), the valley 37 is formed on the end face 31a of the flange 31.
(End surface facing the flange 18) is formed in a concave shape so as to extend in the circumferential direction by a predetermined length, and a plurality of grooves are provided at predetermined intervals corresponding to the ridges 36. The two tapered surfaces 41 in the radial direction abut on the tapered surface 38 of the ridge 36 to perform the rotation transmission in the forward rotation direction X.
And a reverse tapered surface 42 that comes into contact with the tapered surface 39 of the peak portion 36 to transmit rotation in the reverse rotation direction Y. The circumferential length L2 of the valley 37 is the circumferential length L1 of the peak 36.
The taper surface 38 and the reverse taper surface 4 are formed longer.
1, and the tapered surface 39 and the reverse tapered surface 42 are formed so as to be in close contact with each other over substantially the entire surface.

At the time of rotation transmission, predetermined peaks 36 and valleys 37 of the flanges 18 and 31 are opposed to each other.
The driving force is transmitted by meshing so as to be pressed against each other by the urging force of No. 1, but during normal rotation, the tapered surface 38 and the reverse tapered surface 41 are brought into contact as shown in FIG. When the taper surface 38 and the reverse taper surface 41 come into contact with each other, a torque (driving force) in the forward rotation direction X is received. During the reverse rotation, as shown in FIG. The reverse taper surface 42 is engaged so as to abut, and the reverse rotation direction Y
By receiving the torque (driving force), rotational transmission in both forward and reverse directions is performed.

On the other hand, as shown in FIGS. 4 to 6, the end face 36a of the peak 36 and the bottom face 37a of the valley 37 which face each other when the driving force is transmitted extend in the radial direction protruding toward the opposed flanges 31, 18 side. One protruding projection 43 protruding and the projection 43
Two groove-shaped recesses 44 and 4 extending in the radial direction to be fitted in
6 are formed, and the concave portions 44, 46 and the convex portion 43 are arranged so that one of the concave portions 44 or 46 and the convex portion 43 are fitted to each other when driving force is transmitted in both forward and reverse directions.

That is, as shown in FIG. 6A, at the time of forward rotation transmission, the convex portion 43 is fitted with the concave portion 46, and FIG.
As shown in FIG. 7, the convex portion 43 is
The concave portions 44 and 46 are positioned with respect to the convex portion 43 so as to fit with the convex portion 43.
The engaging portions 47 for positioning the ridges 36 with respect to the valleys 37 are constituted by 4 and 46. In the present embodiment, two concave portions 44 and 46 are provided on the end surface 36a of the peak portion 36.
One convex portion 43 is formed on the bottom surface 37a of the valley portion 37. One convex portion 43 is formed on the end surface 36a of the peak portion 36, and two concave portions 44 and 46 are formed on the bottom surface 37a of the valley portion 37, respectively. You may.

Thus, regardless of whether the rotational transmission is performed in either of the forward and reverse rotation directions (the transmission of the driving force), the protrusion 43 is used.
The crest 36 and the valley 37 are fitted by fitting the
(The rotation direction is determined by the contact between the tapered surfaces 38, 39 and the reverse tapered surfaces 41, 42). The play between the groove 36 and the valley 37, that is, the play of engagement of the dog clutch 34 is reduced. Further, as described above, the taper surface 38 and the reverse taper surface 41 and the taper surface 39 and the reverse taper surface 42 are formed so as to be in close contact with each other almost over the entire surface. The driving force is transmitted by abutting on the target area.

Therefore, the noise caused by the backlash during the rotation transmission is reduced, and the load, which is the fluctuation of the load applied to the dog clutch 34 due to the fluctuation of the work load of the work machine 5 (rotary 5a). The transmission efficiency is improved with less clutch slippage due to fluctuations, and the driving force is transmitted by the tapered surfaces 38, 39 and the reverse tapered surfaces 41, 42 abutting on a relatively large area of the same degree in both the forward and reverse rotation directions. Therefore, power transmission with relatively high torque is possible in both rotation directions.

[0020]

According to the structure of the present invention constructed as described above, when transmitting the driving force in both the forward and reverse rotation directions, one of the recesses is convex regardless of the rotation direction. There is an effect that the play between the crests and the valleys that engage with each other is reduced, slippage of the clutch due to load fluctuation is eliminated, transmission efficiency is improved, and noise is reduced.

[Brief description of the drawings]

FIG. 1 is a rear view of a tractor and a left side view of a working machine.

FIG. 2 is a front view of a main part of an auto hitch portion.

FIG. 3 is a side sectional view of a main part of a PTO connection output unit and a transmission unit.

FIGS. 4A and 4B are a rear view and a cross-sectional view taken along line AA of a flange on the side of a PTO connection output unit.

FIGS. 5A and 5B are a front view and a BB cross-sectional view of a flange on the transmission portion side.

FIGS. 6A and 6B are main-portion cross-sectional views of both flanges showing a rotation transmission state in a forward rotation direction and a rotation transmission state in a reverse rotation direction.

FIGS. 7 (a) and 7 (b) are a rear view, a sectional view, a front view and a sectional view of a conventional flange of a PTO connection output section side and a transmission section side.

FIGS. 8A and 8B are cross-sectional views of main parts of both flanges showing a conventional state of rotation transmission in a forward rotation direction and a state of rotation transmission in a reverse rotation direction.

[Explanation of symbols]

 Reference Signs List 16 output shaft (shaft) 18 flange 18a end face 28 drive shaft (shaft) 31 flange 31a end face 34 dog clutch 36 ridge 36a ridge end 37 valley 37a valley bottom 43 convex part 44 concave part 46 concave part 47 engaging part

Claims (1)

[Claims] 1. Flanges (18) and (31) attached to opposed ends of two shafts (16) and (28), and opposed end faces (1) of the flanges (18) and (31).
8a) and (31a) are provided with a concave-convex peak portion (36) and a valley portion (37) that mesh with each other to transmit rotation in both the forward and reverse directions, and have an end surface (36a) and a valley portion of the peak portion (36). In the dog clutch (34) in which both flanges (18) and (31) are urged in the axial direction so that the bottom surface (37a) of the portion (37) is pressed against each other, the ridge portion opposed when the driving force is transmitted. Opposing flanges (31), (1) are provided between the end surface (36a) of the (36) and the bottom surface (37a) of the valley (37).
8) One convex portion (43) projecting to the side and the convex portion (43)
An engaging portion (47) consisting of two concave portions (44) and (46) is provided, and when driving force is transmitted in both forward and reverse directions, one of the concave portions (44) and (46) and the convex portion are provided. (43) A bidirectional transmission dog clutch in which the engaging portion (47) is arranged so as to fit with each other.