JPH048433A - Cam holder tightening device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a device for tightening a cam holder to a cylinder head for assembling a camshaft of an engine such as an automobile or a motorcycle to the cylinder head.

(Prior Art) As is well known, the camshaft of the engine of an automobile, motorcycle, etc. is rotatably held between a cylinder head and a cam holder that is screwed to the cylinder head. After the camshaft is supported on the cylinder head, the cam holder is engaged with the shaft of the camshaft at a predetermined position and tightened to the cylinder head.

In this case, when the camshaft is supported on the cylinder head, the cam of the camshaft usually engages with the valve that is biased upward by a spring and lifts off from above the cylinder head. The work of tightening the cam holder to the cylinder head must be performed with the camshaft pressed against the cylinder head.

It goes without saying that tightening the cam holder can be done manually, but it is desirable to automate this work on engine assembly lines and the like.
A device for tightening such a cam holder is such that the camshaft is supported at approximately a predetermined position on the cylinder head of an engine positioned at a predetermined position, and a pressing jig driven by a cylinder or the like is used to tighten the cam holder. Push the camshaft towards the cylinder head, then
A holding jig holding a cam holder is moved toward the cylinder head, the cam holder is supplied to the tightening point, and then the cam holder is screwed to the cylinder head using a nut runner or the like. Conceivable.

However, since the cam of the camshaft engages in contact with the valve, simply pressing the camshaft against the cylinder head using the pressing jig as described above does not allow the camshaft to The camshaft was easily misaligned from its normal position, and the camshaft was often not installed in the engine at its normal position.

(Question 1!fi to be solved) The present invention eliminates such inconvenience and ensures that the camshaft is positioned at a predetermined position when tightening the cam holder to the cylinder head in order to assemble the camshaft to the engine. An object of the present invention is to provide a device that can tighten the cam holder to a cylinder head.

(Means for Solving the Problem) In order to achieve the above object, the cam holder tightening device of the present invention tightens a cam holder to the cylinder head of an engine such as an automobile or a motorcycle in order to assemble the camshaft to the cylinder head of the engine. A device that removably holds a camshaft supported at approximately a predetermined position on a cylinder head of an engine positioned at a predetermined position;
Further, a shaft positioning means for positioning the camshaft at a predetermined position while pressing the camshaft toward the cylinder head; The cam holder is characterized in that it comprises a holder supply means for supplying the cam holder to the tightening position, and a tightening means for screwing the cam holder supplied to the tightening position to the cylinder head.

Further, the engine is transported and positioned at a predetermined position on the assembly line with the camshaft supported on the cylinder head at approximately a predetermined position toward the width direction of the assembly line, and the shaft positioning Means are provided on both sides of the assembly line so as to be movable toward both ends of the camshaft and to be movable up and down at positions opposite to both ends of the camshaft supported on the cylinder head of the engine positioned at the predetermined position. a pair of shaft engaging jigs that can be freely engaged with and detached from both ends of the camshaft; and the camshaft is moved by moving the two shaft engaging jigs toward both ends of the camshaft and engaging them. A shaft holding means held between both shaft engaging jigs, and by lowering both shaft engaging jigs in the held state, the camshaft is pressed against the cylinder head and positioned at a predetermined position. and a shaft pressing means.

(Operation) According to this means, the camshaft supported at approximately a predetermined position on the cylinder head of the engine is held by the shaft positioning means and is pressed toward the cylinder head and positioned at a predetermined position. In this state, the cam holder is supplied to the cylinder head position by the holder supplying means, and then the cam holder is tightened to the cylinder head by the clamping means, thereby , the camshaft is assembled into the engine's cylinder head.

Furthermore, when the engine is transported and positioned at a predetermined position on the assembly line with the camshaft supported on the cylinder head at approximately a predetermined position in the width direction of the assembly line, The camshaft is held between the pair of shaft engaging jigs that are moved from the side of the assembly line by the shaft holding means toward both ends thereof, and further, in the held state, the camshaft is By lowering both shaft engaging jigs by the pressing means, they are pressed against the cylinder head and positioned at a predetermined position.

(Example) An example of a cam holder tightening device of the present invention will be described with reference to FIGS. 1 to 4. Fig. 1 is a plan view of the entire tightening device, Fig. 2 is an explanatory side view of the entire tightening device, Fig. 3 is a view taken in the direction of the ■ arrow in Fig. 2, and Fig. 4 is a diagram of the tightening device. FIG. 3 is an explanatory diagram for explaining the operation of main parts.

In Figs. 1 and 2, 1 is the engine A shown by the imaginary line in Fig. 2.
A cam holder tightening device (hereinafter simply referred to as the tightening device) installed on the assembly line of Penetrating.

As shown in the second diagram, the engine A is supported at a predetermined position on the conveyor conhair B by a conveyance jig that is conveyed via a base C, and the engine A is supported at a predetermined position on the conveyor conhair B along with the conveyor jig.
The upper part is carried into the frame 2 and positioned at the work station X. In this case, on the cylinder head a of the engine A, there are a pair of camshafts b to be assembled thereto,
camshaft b is supported at approximately a predetermined assembly position, and both camshafts b, b are oriented in the width direction of the assembly line.

The tightening device 1 includes a pair of camshafts b provided opposite each other on both sides of a conveyor belt B in order to position each camshaft b on a cylinder head a of an engine A positioned on a work stage engine X to its assembly position. Shaft positioning means 4 consisting of positioning devices 3, 3, and both camshafts b, b
A holder carrying device 5 is provided on the side of the conveyor container B to carry a predetermined number of cam holders 〇 required for assembling the cam holders into the cylinder head a from the outside of the frame 2.
Then, the Raku cam holder C carried into the frame 2 is supplied to a predetermined assembly position on the cylinder head a. A tightening means 7 is provided on the upper part of the frame 2 for screwing each cam holder C to the cylinder head a.

In FIG. 3, each shaft positioning device 3 of the shaft positioning means 4 has a fixed base 8 fixed to the lower part of the frame 2 on the side of the conveyor B, and a fixed base 8 diagonally upward from the fixed base 8. A tilting base 9 extending toward the tilting base 9, a display base 11 engaged with the tilting base 9 via a rail IO so as to be freely raised and lowered, and a rail 12 on the cough raising base 11. a movable base 13 movably engaged with the shaft positioning device 4 on the opposite side through the A pair of shaft engagement jigs 14 that can be engaged with both ends of the camshaft C
．． 14, a shaft holding means 15 for holding each camshaft b via the shaft engagement jig 14.14, and a shaft pressing means for pressing each held camshaft b against the cylinder head a and positioning it at its assembly position. Means 16 are provided.

In this case, both tilting bases 9.9 are each pivotally connected to a piston rod 17a of a tilting cylinder 17 that is pivotally supported on each fixed base 8, as shown in the second diagram, and is adapted to the type of engine A. By expanding and contracting the piston rod 12a accordingly, each tilting base 9 is tilted in the vertical direction together with the lifting base 11 and the movable base 13 by the same angle θ as the tilt angle θ of the cylinder head a of the engine A. ing. The removable bases 13.13 are each provided at a position facing the cylinder head a of the engine A positioned at the work station It is said to be free.

As shown in the third diagram, the shaft engaging jigs 14.14 are fixedly installed at the upper end of each movable base 13 so as to face each other, and on the cylinder head a positioned between the removable bases 13.13. They are provided at positions facing both ends of each camshaft b. The shaft engaging jigs 14.14 are movable together with each movable base 13 toward the opposing shaft engaging jigs 14, and together with each movable base 13 and each lifting base 11 in the direction of inclination thereof. The contact surface portion 14a is movable up and down, and the contact surface portion 14a contacts the end surface of each camshaft (b) when it is moved towards the camshaft b located between these, and the end portion of each camshaft (b) when lowered in the corresponding state. It includes a locking portion 14b that is locked at the upper end.

The shaft holding means 15 consists of a pair of movable cylinders 18.18 fixedly mounted on both lifter bases 11.11, respectively, facing the movable base 13, and the piston rod 18a of each movable cylinder 18 is connected to each movable base 13. is combined with This shaft holding means 15 is attached to both moving cylinders 1.
By synchronously extending the piston rods 18a, 18a of 8.18, both shaft engagement jigs 14.1
4 together with the movable base 13.13 toward both ends of each camshaft b located between them to bring their abutting parts 14a, 14a into contact; The camshaft b is held between the shaft engagement jigs 14 and 14, and the camshaft b is positioned in its longitudinal direction.

The shaft pressing means 16 consists of a pair of lifting cylinders 19.19 fixedly installed on the sides of both tilting bases 9.9, respectively, facing the lifting base 11, and the piston rod 19a of each cylinder 19 is connected to each lifting base It is coupled to the stand 11. Then, this shaft pressing means 16 presses the piston rod 1 of each lifting cylinder 19 in a state where each camshaft b is held between both shaft engaging jigs 14 and 14 as described above.
By shortening the camshafts 9a, each camshaft b is lowered together with the shaft engagement jig 14°14 toward the cylinder head a and pressed against it, and at this time, the camshafts b are moved as shown by the imaginary line in FIG. It is positioned at a predetermined assembly position on the cylinder head a.

In FIGS. 1 and 2, the holder loading device 5 includes a case body 20 fixed to the lower part of the frame 2 on the side of the conveyor B at a position closer to the rear of the frame 2, and a case body 20 rotated on the case body 20. A turntable 21 is movably supported, and a turntable 21 is movably supported above the turntable 21 via guide rods 22 at the front part inside the frame 2 and the rear part near the outside of the frame 2, respectively. It is provided with a pair of elevating bases 2323 and a pair of movable bases 25.25 supported on both elevating bases 23 via rails 24 so as to be horizontally movable in the front and back direction, and is housed in the case body 20. The turntable 21 is moved by the drive motor 26 (shown by broken lines in FIG.
5 degrees 25, each lifting base 23 is raised and lowered together with each movable base 25 by a pair of lifting cylinders 27.27 (second illustration) fixed to the front and rear of the turntable 21, and each Each movable base 25 is horizontally moved in the front-rear direction between a position directly above each elevating base 23 and a position extending laterally from the directly above position by a moving cylinder 28 fixed to the elevating base 23. I have to.

In this holder carrying device 5, each movable base 25 is moved to a position directly above each elevating base 23 by each moving cylinder 28, and both movable bases 25, 25 are moved to the turntable 21 and the elevating base by a drive motor 26. The base 2323 is rotated 180 degrees at a time and sequentially reversed between a position on the inside side of the frame 2 and a position on the outside side of the frame 2, and the movable base 25 rotated to a position on the outside side of the frame 2 is moved to a moving cylinder. 28, it is horizontally moved in the lateral direction from a position directly above the elevating base 23, and is caused to protrude rearward from within the frame 2.

Then, in the holder carrying device 5, a predetermined number of cam holders 〇 for assembling the camshaft bb to the engine carried into the frame 2 are placed in a predetermined position in a positional relationship corresponding to the assembling position for the engine A. The holder supply plate 29 mounted on the frame 2 is manually placed on the movable base 25 protruding from inside the frame 2, and after this placement, the movable base 25 is moved again to the elevating base 23 by the movable cylinder 28. After moving to the position directly above, both movable bases 25 are rotated 180 degrees by the drive motor 26, and the holder supply plate 29 is carried into the frame 2 together with the cam holder 〇 mounted thereon. In order to transfer the cam holder C on the holder supply plate 29 to the holder supply device 6 (to be described later), the holder supply plate 29 is moved together with the moving base 25 by the elevating cylinder 27 via the elevating base 23 to the holder supply device 6. I am trying to raise it towards.

In FIG. 2, reference numeral 30 denotes a lock cylinder fixed to the case body 20 for locking the turntable 2 after rotation.

Furthermore, a predetermined number of screws d for screwing the cam holder 〇 mounted on the holder supply plate 29 to the cylinder head a of the engine A are loosely inserted in advance.

In FIGS. 1 and 2, the holder supply means 6 is a movable base that extends to the inside of the frame 2 at the rear upper part of the frame 2 above the holder loading device W5 so as to be horizontally movable in the width direction of the assembly line. 31, a movable base 32 engaged with the radial movable base 31 in a vertical position so as to be horizontally movable in the longitudinal direction of the assembly line, and a tilting base 32 extending horizontally from the surface of the movable base 32. A driving device such as a rodless cylinder provided at the rear upper part of the frame 2 includes a freely tilting base 33 and a holder gripping device 35 suspended from the tilting base 33 via a guide rod 34 so as to be freely raised and lowered. 36 horizontally moves the movable base 31 together with the movable base 32, the tilting base 33, and the holder gripping device 35 in the width direction of the assembly line from above the holder loading device 5 to above the conveyor B, and further moves the movable base 31 The movable base 32, together with the tilting base 33 and the holder gripping device 35, is horizontally moved to above the work station X in the longitudinal direction of the assembly line by a drive device 37 provided in the assembly line.

As shown in the fourth diagram, the tilting base 33 is connected to the movable base 32.
The center portion of the end portion of the example is coupled to a rotating shaft 36a of a row reactuator 36 fixed to the back side of the movable base 32 in the width direction of the assembly line, and the row rear actuator 36 It is tilted together with the holder gripping device 35 around the axis of the rotation shaft 36a. Further, the tilting base 33 is integrally provided with a plate 37 disposed parallel to the surface side of the movable base 320, and between the plate 37 and the movable base 32, the rotation shaft 36a is A swing plate 38 whose one end is supported so as to swing freely independently of the tilting base 33 is interposed therearound.

The tilting base 33 is placed in a horizontal position as shown in the second figure when the protrusion 39 protruding from the end of the plate 37 comes into contact with the first stopper 40 protruding from the surface of the movable base 32. The protrusion 39 can freely tilt from the position shown in FIG. 3 to the position shown in FIG. In this case, the other end of the swinging plate 38 is pivotally connected to a piston rod 42a of a swinging cylinder 42 that is swingably supported on the surface of the movable base 320, and By expanding and contracting the piston rod 42a and appropriately changing the position of the second stopper 42 of the swing plate 38, the tilting base 33 is adjusted to the same angle of inclination θ of the cylinder head a of the engine A as shown in the fourth figure. It is made to tilt together with the holder gripping device 35 by an angle θ.

In FIG. 4, reference numeral 43 denotes a lock cylinder fixed to the plate 37 toward the movable base 32 in order to lock the tilting base 33 to the movable base 32 in its inclined position.

In FIG. 4, the holder gripping device 35 includes an elevating base 45 connected to a piston rod 44a of an elevating cylinder 44 fixed to the tilting base 33 facing downward;
A pair of mounting parts 46, 46 that are removably mounted on both sides of the lower surface and extend in the width direction of the assembly line, and both mounting parts 46.
．． A rod 47 is inserted into and fixed to 46 in parallel with the tilting base 33 in the longitudinal direction of the assembly line, and the rod 4
7 is provided with a pair of gripping claws 4B and 48 that are slidably inserted with each mounting portion 46 in between, and these are raised and lowered by extending and contracting the piston rod 44a by the raising and lowering cylinder 44.

In this case, the set of gripping claws 48 and 48 is attached to engine A! [
The number of cam holders 〇 to be installed is provided in a positional relationship corresponding to the assembly position, and the gripping claws 48 of each set are used to open and close the cam holders (opening/closing device 4 provided on the lifting base 45).
9 is engaged.

This opening/closing device 49 includes a guide rod 51 that is slidably inserted into a fixed body 50 that is fixed to the side of the lifting base 45 in parallel with the rod 47, and a guide rod 51 that is fixed to one end of the guide rod 51. It consists of an engaging body 52 provided, an engaging body 53 slidably inserted into the other end, and an opening/closing cylinder 54 fixedly attached to the engaging body 53 facing the engaging body 52.
．． 4B are integrally movably engaged with the engaging bodies 52 and 53 through grooves 52a and 53a formed on the lower surface thereof, and the piston rod (not shown) of the opening/closing cylinder 54 is fixed. It telescopically extends through the body 50 and is coupled to the engaging body 52 . Then, the opening/closing device 49 moves the engaging bodies 52, 53 in opposite directions by expanding and contracting the piston rod 54a of the opening/closing cylinder 54, and moves the gripping claws 4B, 48 along the rod 47 to follow this movement. By sliding the gripping claws 4B, 4
8 is opened and closed, and each cam holder 0 is detachably held between the gripping claws 48 and 48.

In FIG. 4, reference numeral 55.55 is a lever for attaching and detaching the mounting portion 46.46 from the lifting base 45 together with the rod 47 and gripping claws 48. These are exchangeable.

In FIGS. 1 and 2, the means 7 for tightening the cam holder C includes a movable base 56 provided at the front upper part of the frame 2 and extending inside the frame 2 so as to be horizontally movable in the width direction of the assembly line. , a movable base 57 engaged with the movable base 56 in a vertical position so as to be horizontally movable in the longitudinal direction of the assembly line; a tilting base 58 that is tiltably supported by the tilting base 5;
8 and a nut runner 60 which is supported via a rail 59 so as to be freely raised and lowered. The markings are provided in a positional relationship corresponding to the position.

The tightening means 7 is the holder supply means 6.
Similarly, the drive device 6 provided at the front upper part of the frame 2
1, the movable base 56 is horizontally moved in the width direction of the assembly line above the conveyor B together with the movable base 57, the tilting base 58, and the nut runner 60. The movable base 57 is moved horizontally in the longitudinal direction of the assembly line together with the tilting base 58 and the nut runner 60.

Further, this tightening means 7 uses a tilting cylinder 63 fixed to the side of the movable base 570 to move the tilting base 58 together with a nut runner 60 at an inclination angle θ of the cylinder head a according to the type of engine A. The nut runner 60 is raised and lowered by a lifting cylinder 64 fixedly attached to the tilting base 58 facing downward.

In Fig. 1 and Part 2, reference numeral 65 indicates a state in which the camshaft B is assembled to the engine A, as described later, and the camshaft b is connected to other rotating parts such as the transmission shaft of the engine A. This is a frixigin measuring device for rotating via a shaft (not shown) and measuring torque during the rotation.

Next, the operation of the tightening device W1 will be explained.

1 and 2, when the engine A is carried into the frame 2 and positioned at the work station X, the shaft positioning means 4 moves the cam on the cylinder head a of the engine A as described above. Position the shafts b, b at their assembly positions (see Figure 3).

On the other hand, at this time, the holder loading device 5 transports the holder supply plate 29 carrying the cam holder 〇 for assembling the camshafts b, b to the cylinder head a, to the outside of the frame 2 as described above. is carried into the frame 2 together with the movable base 25 placed thereon, and furthermore, at this time, the holder supply means 6 raises its gripping device 35 together with the tilting base 33 to a horizontal position, The gripping device 35 is moved to the base 32 by the drive device 36 and 37.
and the tilting base 33 are horizontally moved directly above the holder supply plate 29.

In this state, the holder carrying-in device 5 raises the holder supply plate 29 toward the gripping device 35 with its lifting cylinder 27, while the holder supply means 6 lifts the gripping device 35 with the lifting cylinder 44 toward the holder. It is lowered toward the supply plate 29, and each cam holder 〇 on the holder supply plate 29 is positioned between the open gripping claws 48, 48 of each set of the gripping device 35.

Next, the gripping device 35 closes each set of gripping claws 48, 48 as described above with its opening/closing device 49, thereby holding each cam holder 〇 in each set of gripping claws 48, 48.
Hold it in between.

After the gripping, the holder supply means 6 raises the gripping device 35 again to detach each cam holder 〇 from the holder supply plate 29, and further positions the gripping device 35 at the work station X in the raised state. After horizontally moving above the cylinder head a of the engine A, as shown in FIG. and the cough gripping device 35 is opposed to the cylinder head a directly above the cylinder head a in the direction of inclination. At this time, each cam holder C held by each set of gripping claws 48, 48 of the gripping device 35 faces a predetermined assembly position on the cylinder head a.

Next, the holder supply means 6 lowers the gripping device 35 toward the cylinder head a, and places each of the cam holders C gripped by the gripping device 35 onto the shaft on the cylinder head a, as shown in phantom lines in FIG. It is engaged with each cam shirt (b) positioned by the positioning means 4, and placed on the cylinder head a at its predetermined assembly position. After opening the pair of gripping claws 48.4B to release the grip on each cam holder 〇, the gripping device 35 is raised and removed from each cam holder C. After the detachment, the holder supply means 6 returns the gripping device 35 to a horizontal position,
Furthermore, in order to pick up the cam holder 〇 to be assembled into the engine A to be carried into the frame 2 next, the gripping device 35 is again moved above the holder carrying device 5.

On the other hand, in FIGS. 1 and 2, during the above operation, the tightening means 7 moves each nut runner 60 in a raised state by means of its driving devices 61 and 58. At the same time, the cam holders C are placed on the cylinder head a of the engine A and the gripping device 35 is removed from the cylinder head a, as described above. The inclination of the cylinder head a is such that each nut runner 60 is inclined by an angle θ,
One of the cam holders 0 on the cylinder head a is horizontally moved directly above each of the ridges d which are loosely inserted in advance.

The tightening means 7 then tighten each nut runner 60.
is lowered toward each screw d of the cam holder 〇 by the lifting cylinder 63 and engaged with it, and then each nut runner 60 tightens each screw d all at once, thereby moving the cam holder C into the cylinder. Tighten the screw to head a. Then, repeat this screw tightening work for all the cam holders C on the cylinder head a, and when all the cam holders 〇 are screwed to the cylinder head a, each camshaft b is assembled to the cylinder head a. It will be done.

Incidentally, during this screw tightening work, the tightening means 7 presses each cam holder 0 against the cylinder head a using a holder holding jig (not shown).

After this, the tightening means 7 retracts each nut runner 60 as described above in order to assemble the camshaft b to the engine A that is then carried into the frame 2, and also tightens the shaft. The positioning means 4 moves the shaft engaging jig 14 by an operation opposite to that when positioning the camshaft b on the cylinder head a as described above.
is removed from the camshaft b. Then, the engine A to which the camshaft b is assembled has the camshaft b
is rotated by the friction measuring device and torque measurement is performed, and then carried out of the frame 2 by the conveyor B.

(Effects) As is clear from the above description, the cam holder of the present invention can be tightened by tightening the camshaft supported at approximately a predetermined position on the cylinder head of an engine positioned at a predetermined position. When assembling the cam holder to the cylinder head, the camshaft is held by the shaft positioning means and positioned at a predetermined position while being pressed toward the cylinder head, and in this state, the cam holder is moved into the cylinder by the holder supply means. The camshaft is securely placed in a predetermined assembly position on the cylinder head by tightening the camshaft onto the cylinder head by screwing the cam holder onto the cylinder head. It can be assembled in the attached position.

Then, on the assembly line, the engine to which the camshaft is to be assembled is transported to a predetermined position and positioned with the camshaft supported on the cylinder head at approximately a predetermined position in the width direction of the assembly line. When the camshaft is assembled, a pair of shaft engaging jigs provided on both sides of the assembly line are moved toward both ends of the camshaft by shaft holding means, and the camshaft is held between the two shaft engaging jigs. By doing this, the longitudinal position of the camshaft can be positioned at a predetermined position on each cylinder head with respect to the cylinder head. After the clamping, both shaft engaging jigs are lowered by the shaft pressing means. The camshaft can be easily and reliably positioned at a predetermined assembly position on the cylinder head by simply pressing the camshaft onto the cylinder head, and the structure of the shaft positioning means is relatively simple. It can be done.

[Brief explanation of the drawing]

FIG. 1 is a plan view of the entire tightening device for a cam holder of the present invention, FIG. 2 is an explanatory side view of the entire tightening device, FIG. 3 is a view taken in the direction of the ■ arrow in FIG. 2, and FIG. FIG. 3 is an explanatory diagram for explaining the operation of the main parts of the tightening device. l...Cam holder tightening device 4...Shaft positioning means 6...Holder supply means 7...Tightening means 14...Shaft engaging jig 15...Shaft holding means 16... ...Shaft pressing means A...Engine a...Cylinder head b...Camshaft C...Cam holder

Claims (1)

[Scope of Claims] 1. A device for tightening a cam holder to a cylinder head of an engine such as an automobile or a motorcycle, in order to assemble a camshaft to the cylinder head of the engine, which is mounted on the cylinder head of the engine positioned at a predetermined position. shaft positioning means for removably holding a camshaft supported at approximately a predetermined position on the cylinder head, and for positioning the camshaft at a predetermined position while pressing the camshaft toward the cylinder head; a holder supplying means for supplying the cam holder to a tightening position on the cylinder head in a state in which the cam holder is positioned at a predetermined position; and a tightening means for screwing the cam holder supplied to the tightening position to the cylinder head. A cam holder tightening device characterized by: 2. The engine is transported and positioned at a predetermined position on the assembly line with the camshaft supported on the cylinder head at approximately a predetermined position toward the width direction of the assembly line, and the shaft positioning Means are provided on both sides of the assembly line so as to be movable toward both ends of the camshaft and to be movable up and down at positions opposite to both ends of the camshaft supported on the cylinder head of the engine positioned at the predetermined position. a pair of shaft engaging jigs that can be freely engaged with and detached from both ends of the camshaft; and the camshaft is moved by moving the two shaft engaging jigs toward both ends of the camshaft and engaging them. A shaft holding means held between both shaft engaging jigs, and by lowering both shaft engaging jigs in the held state, the camshaft is pushed toward the cylinder head and positioned at a predetermined position. 2. The cam holder tightening device according to claim 1, further comprising a shaft pressing means.