JPS60527B2 - Assembling device for protruding biased plunger - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a silk applicator that easily suppresses and releases the biasing force of a plunger that is always biased in the ejecting direction.

Conventionally, plungers used in a protruding biased state were either disassembled and transported after removing the protruding biasing force, or were transported by being stuffed into a container, and when attached to other equipment, the plunger was manually pushed in. For example, when assembling a tensioner into the engine from outside the engine case in the final process of engine assembly, such as a tensioner for an engine timing chain,
It is difficult to assemble the tensioner to the engine using the conventional mounting operation, since it is necessary to release the biasing force from the plunger after inserting the tensioner body into the engine case. As shown in FIG. 1, the tensioner has a plunger chamber 2 that is open at both ends in the tensioner body 1, and a spring compression screw 3 is carved into the inner periphery of the entrance at one end of the plunger chamber 2. A plunger 4 is inserted so that it can move freely in the direction of the bag, and a large number of locking teeth 5 are carved in the circumferential direction on a flat surface formed on a part of the circumferential surface of the plunger 4 in the generatrix direction. It is biased by a spring 6 in the locking direction so as to lock on the stop tooth 5 and allow the plunger 4 to slide in the protruding direction, and slide in the opposite direction to the pushing direction of the plunger 4, that is, the protruding direction. A claw member 7 that prevents movement is pivotally supported on the tensioner body 1, and a tensioner shoe (not shown) is provided at the protruding tip of the plunger 4 to press against the timing chain (not shown) and apply a constant tension to the timing chain. ) is attached, and a coil spring 9 as a biasing spring, which is longer than the length of the hole, is placed in a bag in a bottomed circular hole 8 bored in the axial direction of the plunger 4, and the spring is compressed through a gasket 10. A bolt 12 having a threaded portion 11 that engages with the screw 3 is screwed onto the tensioner body 1, and the coil spring 9 is enclosed in the plunger chamber 2 in a compressed state between the plunger 4 and the bolt 12. Therefore, the plunger 4 is always urged in the direction of protruding from the plunger chamber 2 by the coil spring 9 in a compressed state, and unless the plunger 4 is prevented from protruding by hand, the plunger will be pushed out of the plunger chamber 2 by the coil spring 9. It jumps outside and leaves plunger chamber 2, ending the process. Therefore, as mentioned above, it becomes difficult to attach the timing chain to the timing chain installed inside the engine case. In particular, since the tensioner is inserted into a motorcycle engine from outside the engine case after the engine is assembled, it cannot be inserted unless the plunger is prevented from popping out. Therefore, the following proposal has been made to make it easier to attach paper to the tensioner. '1) First, insert only the tensioner body 1 with the plunger 4 inserted into the engine case E as shown in the arrow direction in Fig. 1, bring the tension boot shoe into contact with the chain, and then insert the coil spring. A lacing method in which the bolt 12 is screwed onto the tensioner body 1, the coil spring 9 is compressed, the plunger 4 is biased in the projecting direction, and the tensioner shoe is pushed against the chain.

(2) As shown in FIG. 2, a side pin 13 is provided protruding from the plunger 4, and a hook 14 that engages and disengages from the pin 13 is rotatably pivoted to the tensioner body 1. 14
is locked to the side pin 13 to prevent the plunger 4 from flying out, and then the plunger 4 is inserted into the engine case, and as the plunger 4 moves back in the direction of arrow A due to backlash vibration of the timing chain, the side pin 13 is The tapered cam surface 15 of the hook 14 is pushed down to be removed from the side pin 13, and the plunger 4 is projected by the biasing force of the coil spring 9, pressing against the timing chain and applying a constant tension to the chain.

'3l As shown in Fig. 3, the tensioner body 1 is provided with a screw hole that penetrates into the plunger chamber 2, and the bolt
Means for preventing the plunger 4 from popping out by screwing in the bolt 16 to press the plunger 4, and releasing the popping out of the plunger 4 by unscrewing the bolt 16 after rough fitting. ■ As shown in FIG. 4, a stopper 17 that prevents the rotation of the claw member 7 provided on the tensioner body 1 is inserted into the rear part of the claw member to prevent the plunger 4 from flying out.
An assembling means that allows the plunger 4 to stand up and lock onto the locking teeth 5, and then removes the stopper 17 after assembling to allow the plunger 4 to pop out.

However, in method {1} above, after the tensioner body is attached, the bolt amount 2 must be compressed against the force of the spring 9 and screwed into the spring compression screw 3 of the tensioner body, so the bolt screw The work of aligning the portion 11 with the spring compression screw 3 of the tensioner body is hindered by the compression reaction force of the spring 9 and cannot be easily performed.

Further, the means [2-] is the side pin 1 together with the plunger 4.
3 is inserted into the engine case E, ``a space for inserting the side pin 13 is required on the engine side, which limits the degree of freedom in design and requires securing extra space.More importantly, the tensioner There is a drawback that it is not possible to confirm whether the hook 14 has come off from the side pin 13 due to the vibration of the chain after it has been inserted into the main body, and if it does not come off, the specified tension is not applied to the timing chain and the sprocket that is suspending the chain. There is a risk that the chain may become disengaged from the wheel, resulting in extremely poor reliability.Furthermore, with the method of {8}, the bolt 16 must be unscrewed after the tensioner body 1 is inserted into the engine case E. Not only does it have the disadvantage of requiring an extra space to pull out the bolt corresponding to the length of the bolt, but it is also extremely weak since the force that suppresses the protruding force of the plunger 4 is applied from the side of the plunger, so it is not used in tensioners. Since coil springs generally have high elasticity, it is difficult and less reliable to reliably prevent the plunger 4 from popping out. Since it is not possible to insert your hands or tools, after inserting the tensioner body into the engine case,
It is impossible to remove the stopper 7. As mentioned above,
Each of the proposals has many problems in terms of reliability and difficulty in insertion work.

The present invention eliminates the conventional drawbacks and solves the problems of the above-mentioned proposals, and provides a rough setting device for a protruding biased plunger that is easy to transport and insert, easy to assemble, and reliable. An embodiment of the timing chain tensioner inserted into the engine case will be described using the same reference numerals for the same components as those shown in FIGS. 1 to 4. FIGS. 5 a and b
, c and d are the first embodiment of the present invention, and the bolt 1
2 includes, in addition to a threaded portion 11 screwed into the spring compression screw 3, a reverse threaded portion 20 of the threaded portion il, as shown in FIG.
In other words, if the threaded part 11 is a right-handed thread, the reverse threaded part 20
is a left-handed thread, and if threaded part 11 is a left-handed thread, it is a reverse threaded part 2.
A right-hand thread is carved on the inner periphery of the entrance end of the bottomed hole 8 of the plunger 4, as shown in Figure b.
A plunger protrusion prevention screw 21 into which the plunger is screwed is provided.

Therefore, the spring compression screw 3 and the plunger protrusion prevention screw 21 have opposite threads. Therefore, as shown in Figure c, before inserting the tensioner body 1 into the engine case E, press the tensioner body 1 while holding the plunger 4 from protruding.
Screw the threaded part 11 of the bolt into the spring compression screw 3 of
If the bolt 12 is rotated in the opposite direction at the time when the reverse threaded portion 20 of the bolt comes into contact with the plunger protrusion prevention screw 21 carved into the plunger 4, the bolt 12 moves in the unthreading direction relative to the tensioner body 1. , while the reverse threaded part 2
0 is screwed into a plunger protrusion prevention screw 21 of a non-rotatable plunger, and the plunger 4 and bolt 12 are fastened and integrated with the coil spring 9 compressed and enclosed. Therefore, after the plunger 4 and the bolt 12 are fastened together, the plunger 4 does not need to be prevented from protruding by external force.
Since there is no danger that the tensioner will fly out of the plunger chamber 2, in this state, the tensioner body can be freely transported and inserted into other equipment as a whole as shown in Figure d. Therefore, after inserting the tensioner body 1 in which the plunger 4 and the bolt 12 are fastened and integrated from the outside into the engine case E', the threaded portion 11 of the bolt is screwed into the spring compression screw 3 of the tensioner body. bolt 1
When the bolt 2 is rotated, the oppositely threaded portion of the bolt 2 is rotated in the direction in which it is unscrewed from the plunger protrusion prevention screw 21 of the plunger 4, and the connection between the plunger 4 and the bolt 12 is released. 4 is a coil spring 9
As a result, the bolt 12 moves in a direction to pop out from the plunger chamber 2, while the bolt 12 is screwed into the tensioner main body 1 and moves in a direction to further press the coil spring 9.

Therefore, when the tensioner main body 1 is inserted into the engine case E, the plunger and the tensioner main body are integrated, making it easy to insert the tensioner main body 1. After the tensioner main body 1 is inserted, by rotating the bolt, the plunger will pop out due to the biasing force of the coil spring. At the same time, the tensioner shoe is compressed by the coilover bolt and can be reliably pressed against the timing chain to apply a predetermined tension to the chain.

FIG. 6 shows a second embodiment of the present invention, in which the reverse threaded portion 20 in FIG. A reverse threaded portion 20' is carved on the outer periphery of the tip, and a plunger protrusion prevention screw 21' that is screwed into the reverse threaded portion 20' is further drilled at the bottom of the bottomed hole 8 formed in the plunger 4. The bolt 12 is screwed into the tensioner body 1 while the plunger 4 is prevented from protruding by an external force in the same manner as in the first embodiment, and a guide hole protruding from the bolt is formed in the hole 8'. Reverse threaded part 20' carved at the tip of 12'
When the bolt is pressed against the plunger protrusion prevention screw 21' in the threaded hole 8' of the bottomed hole of the plunger, the bolt is rotated in the opposite direction to connect the plunger protrusion prevention screw 21' and the reverse groove engraved on the bolt guide punch. The plunger 4 and the bolt 12 are fastened together with the coil spring 9 compressed in the bottomed hole 8 of the plunger L. Then, the plunger 4 and the bolt 12 are integrated into the L. As in the case of the first embodiment, the bolt is rotated to release and release the screw engagement between the plunger 4 and the bolt, thereby causing the plunger 4 to fly out and operate.

Note that the length of the threaded portion may be short since it is sufficient to screw the plunger 4 into the reverse threaded portion carved into the bolt. As described above, in the present invention, it is extremely easy to select whether to compress the coil spring and cause the plunger to pop out by rotating the same bolt in the forward and reverse directions, or to prevent the plunger from popping out while maintaining the compressed state of the coil spring. Since the plunger can be operated easily when the plunger is prevented from flying out, it is easy to transport and handle the plunger. Even in such cases, the state where the plunger is prevented from protruding can be easily released by rotating the bolt in the opposite direction. Therefore, in the final process of engine assembly, the plunger of the tensioner can be positioned from outside the engine case into the engine case. The assembly work of inserting and installing can be done easily, and the plunger is screwed in by rotating the bolt in the opposite direction, and the plunger is unscrewed by rotating the bolt in the forward direction while compressing the coil spring, making it invisible to the naked eye. The plunger can be unscrewed reliably even in such locations, and the overall size of the plunger has been reduced to save space for threading.

[Brief explanation of the drawing]

Figures 1 to 4 show a conventional engine timing chain tensioner. Figure 1 is an exploded front view, Figure 2 is a front view of main parts, and Figures 3 and 4 are front sectional views. 5 and 6 show tensioners for engine timing chains according to the first and second embodiments of the present invention, and FIG.
is a front sectional view of the bolt, b is a front sectional view of the main part of the plunger, c is a front sectional view when the plunger can be ejected, d is a front sectional view when the plunger is prevented from ejecting, and Figure 6 is a front sectional view when the plunger is able to eject. It is a diagram. 1...Tensioner body, 2...Plunger chamber, 3...Spring compression screw, 4...Plunger,
9...Biasing spring, 11...Screw part, 12...
...・Bolt, 20, 20'... Reverse threaded part, 21, 21
'・・・・・・Plunger protrusion prevention screw. Figure 1 Figure 2 Figure 3 Figure 4 Figure 6 Figure 5

Claims (1)

[Claims] 1. A spring compression screw is carved into the inner periphery of one end opening of a plunger chamber with both ends open, and the spring compression screw is inserted into the plunger which is inserted into the plunger chamber so as to be able to protrude freely from the other end opening and not rotate. and a reverse-threaded plunger protrusion prevention screw, and a bolt having a threaded portion that is screwed into the spring compression screw and a reversely threaded portion that is screwed into the plunger protrusion prevention screw is screwed into the plunger chamber and the plunger. An apparatus for assembling a protruding biased plunger, in which a plunger protruding biasing spring is enclosed in a compressed state in a plunger chamber between the bolt and the plunger.