JPH02275118A - Drive transmission mechanism - Google Patents

Abstract

PURPOSE:To prevent the leakage and volatilization of lubricant applied to a sliding part by hermetically sealing an installed part with a covering member to cover the outer peripheral side of a clutch spring all around and hermetically seal a connecting part. CONSTITUTION:The outer periphery of a clutch spring 3 which operates and connects a driving gear 1 and a fixed boss 2 is covered all around with a control ring 5, both ends of which are projected far out from the clutch spring 3. to form fitting parts 6, 7 with the outer periphery of the drive gear 1 and the fixed boss 2. A sealing member 8 is placed in the gap between the fitting parts 6, 7 and the step parts 1B, 2B of the drive gear 1 and the fixed boss 2 to seal off lubricant 9 inside the control ring 5, so that the leakage and volatilization of the lubricant 9 applied to the sliding part of the clutch spring 3 as well as the occurrence of frictional sound and 'stick-slip' can be prevented.

Description

[Detailed description of the invention] (Industrial application field) The present invention is applicable to, for example, electrophotographic copying machines and printing machines.

The present invention relates to a drive transmission mechanism applied to sheet conveyance systems of various printers and various rotary drive devices, and particularly relates to a drive transmission mechanism that uses a spring to perform a clutch action.

(Prior Art) Conventionally, as this type of drive transmission mechanism, there is one shown in FIG. 5, for example. That is, this mechanism switches the transmission of driving force via a coiled clutch spring lOO, and is composed of a driving side member 101 and a driven side member 102. Drive side member 101 and driven side member 1
02 is coaxially arranged so as to be relatively rotatable, and the axially opposing portion thereof has a cylindrical portion 101A having the same diameter.

102A is provided.

The clutch spring 100 has both cylindrical parts 101A, 1
It is fitted so as to straddle 02A.

The driving side member 101 and the driven side member 102 are driven ji
d1103, the driving side member 101 is in a free state with respect to the driven shaft 103, and the driven side member 102 is fixed to the driven shaft 103.

Further, a hook 104 is provided at one end of the clutch spring 100, and is engaged with a control ring 105.

Therefore, the control ring 105 is controlled by a solenoid (not shown) or the like.
When the clutch spring 100 is stopped, the hook 104 side end portion of the clutch spring 100 is loosened, a gap is opened between the clutch spring 100 and the cylindrical portion 101A, and only the driving side member 101 rotates freely and no driving force is transmitted to the driven side member 102.

Furthermore, when the control ring 105 is set in the free state, the drive side member 1
01 The driven member 102 rotates in the direction in which the clutch spring 100 is tightened, the driving force is transmitted to the driven member 102, and the driven shaft 103 rotates.

The clutch spring 100 is each cylindrical portion 101A of the driving side member lot or the driven side member 102.

Since the driving force is transmitted by tightening and loosening the outer circumference of the clutch spring 102A, a lubricant 106 such as grease is applied to the sliding contact portion of the clutch spring 100 to prevent the clutch spring 100 from being worn out. At the same time, the transmission force was switched smoothly.

(Problem to be Solved by the Invention) However, in the case of the above-mentioned prior art, the control ring 10
The fitting part between 5 and the drive side member lO1 is a loose fit, and there is a gap 1.
07, the lubricant 106 leaks or evaporates from the gap 107 over a long period of time, resulting in dry smoke on the sliding surface of the clutch spring 100.

Therefore, there is a problem in that the clutch spring 100 is in a solid contact state and a vibration noise is generated due to listex slip caused by eight frictions, making it impossible to smoothly switch the clutch.

The present invention has been made to solve the problems of the prior art described above, and its purpose is to maintain a good lubrication state of the clutch spring for a long period of time by preventing lubricant leakage. The object of the present invention is to provide a drive transmission mechanism.

(Means for Solving the Problem) In order to achieve the above object, in the present invention, a driving side member and a driven side member provided coaxially are connected in one direction via a coiled clutch spring. Connected only to the rotating part,
In a drive transmission mechanism in which a lubricant is applied to a connecting portion of a clutch spring, the outer peripheral side of the clutch spring is entirely covered;
The present invention is characterized in that a covering member is provided to seal the Craft spring connection portion.

Alternatively, the covering member may include a control ring that is engaged with one end of the clutch spring, and a sealing member that seals the fitting portion that fits on the outer periphery of the drive side and driven side members of the control ring. good.

(Function) In the drive transmission mechanism configured as described above, since the connection portion of the clutch spring is sealed by the covering member, leakage and volatilization of the lubricant are prevented, and the slipperiness of the clutch spring is maintained over a long period of time.

Furthermore, in a device that uses a control ring to switch drive transmission, the control ring can also be used as a covering member.

(Example) The present invention will be explained below based on the illustrated example. Third
The drawings and FIG. 4 show a paper feeding section of a laser beam printer or the like to which a drive mechanism according to an embodiment of the present invention is applied. Reference numeral 10 designates a paper feeding roller having a half-moon shape in cross section, which comes into contact with the uppermost layer of a plurality of sheets S and feeds the sheets S one by one. This paper feed roller 10 operates intermittently, and feeds the paper 11 to the registration roller 12 disposed downstream of the paper feed roller 10 in the feeding direction, and when the paper 11 has been fed to the registration roller 12, the cutting unit 104 moves to the paper section. It is designed to stop facing the side. This intermittent control of the paper feed roller 10 is performed by the drive transmission mechanism of the present invention.

As shown in FIG. 1, the drive transmission mechanism C generally includes a drive gear l as a drive side member, a fixed post 2 as a driven side member, and a coiled clutch spring 3 for operatively connecting both members. A device drive gear 1 and a fixing bolt 2 are coaxially inserted into a roller shaft 13 of a paper feed roller 10, and a fixing post 2 is inserted into a fixing screw 20.
The drive gear 1 is integrally fixed to the roller shaft 13 by means of the roller shaft 13, etc., and the drive gear 1 is rotatable with respect to the roller shaft 13.

On the other hand, the drive gear l and the fixed post 2 have cylindrical parts IA and 2.
The cylindrical parts IA and 2A have the same diameter and are coaxially arranged close to each other, and the clutch spring 3 is fitted across both cylindrical parts LA and 2A. .

The drive gear 1 is operatively connected to a drive motor (not shown) via a transmission gear 16 and is rotationally driven.

On the other hand, one end of the clutch spring 3 is bent in the direction of the roller shaft 13 to form a first hook 31, and this first hook 31 is connected to a groove 41 formed in the flange 4 of the fixed post 2.
is engaged in.

Further, the other end of the clutch spring 3 is provided with a second hook 32 that is bent radially outward perpendicular to the roller shaft 13, and this second hook 32 is connected to the clutch spring. Notch part 51 of control ring 5 attached to the outer periphery of 3
is engaged with.

This control ring 5 is provided with a pawl portion 52, and the actuator 15 of the electromagnetic solenoid 14 selectively approaches and separates from the pawl portion 52.

The control ring 5 is a cylindrical member that covers the entire outer periphery of the clutch spring 3, and its both ends protrude longer than the length of the clutch spring 3, and are annular fittings that are fitted to the fixed post 2 and the outer periphery of the drive gear 1, respectively. Sections 6 and 7 are shown.

In the drive gear 1, the portion into which the fitting portion 6.7 fits is stepped, and the fitting portion 6 of the control ring 1 fits into the outer periphery of the stepped portion IA.

On the other hand, the fixed post 2 also has a stepped shape, with a stepped portion 2B provided between the cylindrical portion 2A and the flange portion 4.
A fitting portion 7 at one end of the control ring 5 is fitted to B.

The fitting portions 6, 7 and the step portion IB at both ends of the control ring 5,
2B, and a sealing member 8 is interposed to seal this gap liquid-tightly.

The seal member 8 is for sealing a lubricant 9 such as grease applied to the sliding parts of the clutch spring 3 and the drive gear 1. This sealing member 8 is made of felt, for example.
It is fixed to the drive gear 1 and the fixed post 2 with double-sided tape or the like, and is prevented from rotating along with the control ring 5.

In this embodiment, both ends of the control ring 5 are sealed by seal members 8, so that the lubricant 9 in the control ring 5 can be completely sealed, and the slipperiness can be maintained for a long period of time.

Further, in FIG. 2, a small hole 53 is provided in the control section 5. Although the sealing performance of the control ring 5 is somewhat impaired, there is an advantage that grease can be injected through the small hole 53 at the end of one assembly process. This small hole 53 is sealed by a grease plug 54 after injecting a lubricant such as grease.

In general, the above system [! If 5 is made of a transparent material such as polycarbonate, the state of the lubricant injected inside can be visually checked, and the work can be carried out efficiently.

In this embodiment, a case has been described in which the fitting portion of the control ring 5 is sealed to seal the lubricant, but a case in which driving force is simply transmitted in one direction without using the control ring 5 may also be described. Applicable.

In this case, a covering member may be separately provided to cover the outer peripheral side of the clutch spring, and the contact portions between the driving side member and the driven side member at both ends of the covering member may be sealed.

In addition, in this embodiment, an example in which the present invention is applied to drive control of a paper feed unit of a laser beam printer, etc. has been described, but the present invention is not limited to this, and the present invention is not limited to this, but can be applied to document feeding mechanisms, various conveyance systems, and various rotary drive devices. It is generally applicable.

(Effects of the Invention) The present invention has the above-described structure and operation, and since a covering member is provided to seal the mounting portion of the clutch spring, leakage and volatilization of the lubricant applied to the sliding portion of the clutch spring can be prevented. The slipperiness of the clutch spring can be maintained for a long period of time, and friction noise and sticks can be prevented for a long time.

Claims (2)

[Claims] (1) A drive in which a driving side member and a driven side member that are coaxially connected are connected so as to be relatively rotatable in only one direction via a coiled clutch spring, and a lubricant is applied to the connecting part of the clutch spring. A drive transmission mechanism, characterized in that the transmission mechanism comprises a covering member that covers the entire outer circumference of the clutch spring and seals the clutch spring connecting portion. (2) The covering member is a control ring with which one end of the clutch spring engages, and the fitting portion of the control ring that fits on the outer periphery of the driving side and driven side members is sealed with a sealing member. The drive transmission mechanism described in .