JPH04124322U - Intershaft spacer - Google Patents

Abstract

(57) [Summary] [Purpose] To improve the wear resistance of the fitting part with the shaft, and to maintain the accuracy of the distance between the shafts of two rotating drums over a long period of time. [Structure] The shaft is rotatably fitted to one of a pair of rotating drums arranged parallel to each other and comes into contact with the outer peripheral surface of the other drum, thereby defining the distance between the shafts of these drums. The inter-shaft spacer for the purpose of A plurality of protrusions that can be rotated are integrally formed, and when the inner and outer members are combined so as to be able to freely rotate relative to each other, this protrusion engages with one of the other members to prevent the two members from coming off. Configure.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

The present invention is designed to be able to connect the photosensitive drum and toner drum of an electronic printer, for example. An inter-shaft spacer to define the gap between a pair of rotating drums arranged parallel to each other. It is related to.

0002

[Conventional technology]

Fine colored powder called toner used in electronic copying devices and laser printers In printers that use static electricity to attract materials, tiny gaps are created on the surface of the photosensitive drum. A type in which the toner supply drums are placed opposite each other is known. This photosensitive As shown in Fig. 1, the structure that defines the gap size between the drum and the toner drum is as follows. A spacer roller 3 (from the radius of the photosensitive drum) for defining the distance between the shafts is attached to the shaft 2 of the photosensitive drum 1. (having a radius as large as the required gap size) is fitted rotatably, and this spacer By abutting the roller 3 against the outer peripheral surface of the toner drum 4, the two drums 1 and 4 are separated. There is a device that allows the gap between them to be defined and maintained accurately.

0003

[Problem that the idea aims to solve]

Conventionally, such spacer rollers were fitted directly onto the shaft of the photosensitive drum. This is common, and the fitting hole may wear out and expand due to sliding contact with the metal shaft. There was. As a result, play occurs between the shaft and the spacer roller, and the distance between the shafts cannot be adjusted accurately. There was an inconvenience that the degree of oxidation decreased.

0004 The present invention was devised in order to eliminate such disadvantages of the conventional technology, The main purpose is to prevent wear on the fitting part with the shaft and maintain the accuracy of the distance between the shafts over a long period of time. An object of the present invention is to provide an improved inter-shaft spacer that can be maintained at the same time.

[0005]

[Means to solve the problem]

According to the present invention, this purpose is achieved by a pair of rotating drives arranged parallel to each other. It is rotatably fitted onto one shaft of the drum and comes into contact with the outer circumferential surface of the other drum. Inter-axle spacer to define the inter-axle distance of these multiple drums by The inter-shaft spacer is made of a synthetic resin material having self-lubricating properties, and An inner member that is integrally coupled to the shaft, and an arm that can be rotatably engaged with the inner member. an outer member, and either the inner member or the outer member. A plurality of protrusions whose free ends can be elastically deformed in the radial direction are integrally formed on one side. When the inner and outer members are combined with each other, the protrusion engages with one of the other members. The structure is characterized in that relative axial displacement of both members is prevented by This is achieved by using an inter-shaft spacer.

[0006]

[Effect]

According to such a configuration, the relatively rotating portions come into contact with the synthetic resin materials. Also, there is no way to prevent the two parts from coming off due to the protrusion that is integrally formed on one of the parts. It will be done.

[0007]

【Example】

The configuration of the present invention will be explained in detail below based on specific embodiments shown in the attached drawings. explain.

[0008] FIG. 1 shows a photosensitive drum 1 and a toner drum 4 of an electronic printer to which the present invention is applied. This diagram schematically shows the relationship between The photosensitive drum 1 and toner drum 4 are They face each other with a small gap (d dimension, for example, about 1 mm). photosensitive drum A spacer roller 3 is fitted onto the shaft 2 of the drum 1. This spacer roller 3 , which is larger than the radius of the photosensitive drum 1 by the same dimension as the minute gap mentioned above. By contacting the outer circumferential surface of the axial end of the toner drum 4, the photosensitive drum 1 and the drum are brought into contact with each other. It functions to maintain a constant gap with the inner drum 4.

[0009] By the way, since the rotational speeds of the photosensitive drum 1 and the toner drum 4 are different, The shaft 2 of the ram and the spacer roller 3 rotate relative to each other, but the shaft 2 of the photosensitive drum and the spacer roller 3 rotate relative to each other. When the part between the roller 3 and the roller 3 wears out, the shaft between the photosensitive drum 1 and the toner drum 4 Distance accuracy decreases. Therefore, it is desirable that this part be as hard to wear as possible. stomach. Therefore, in the present invention, the spacer roller 3 is fitted onto the shaft 2 of the photosensitive drum. Improvements were made to the joints.

0010 2 and 3 show a first embodiment of an improved spacer roller 3. . This spacer roller 3a is made up of two parts, an inner member 5 and an outer member 6. It is injection molded using oil-impregnated polyacetal resin material.

[0011] The inner member 5 has a disk shape, and has a center that receives the shaft 2 of the photosensitive drum at its center. A hole 7 is formed, and a groove 8 having a rectangular cross section is formed all around the outer circumferential surface of the hole 7. Ru.

0012 The outer member 6 is basically ring-shaped and rotates freely around the outer peripheral surface of the inner member 5. Formed at positions that divide the circumference into three equal parts (3 places) so that it can be received relatively closely at the same time. The inner circumferential surface 9 has a partially annular shape, and each partially annular inner circumferential surface at one axial end. 9 and a partial circumferential flange 10 formed radially inward at a position connected to the other An arcuate protrusion 11 formed as an extension of each partial annular inner circumferential surface 9 on the axial end surface, and others. radially diagonally inward from one circumferential end of each partial annular inner circumferential surface 9 at one axial end The angular protrusion 12 is provided with a angular protrusion 12 extending from the bottom. and adjacent to each partial annular inner circumferential surface 9 By cutting out the outer peripheral side of each angular protrusion 12, these The free end of the angular projection 12 is configured to elastically deform outward in the radial direction ( (shown in imaginary lines in Figure 3). Note that the angular protrusion 12 is approximately equal to the inner width of the groove 8 of the inner member 5. They have equal width dimensions.

[0013] In this spacer roller 3a, each angular protrusion 12 of the outer member 6 is arranged in a radial direction. The inner member 5 is fitted into the partially annular inner circumferential surface 9 while being elastically deformed outwardly, and By engaging each angular protrusion 12 with the groove 8 of the inner member 5, each flap is The hinge 10 and each angular projection 12 cooperate to maintain the axis of the inner member 5 relative to the outer member 6. At the same time, the inner circumferential surface 9 of the outer member 6 is prevented from coming off in the direction. The inner member 5 is rotatably held.

[0014] 4 and 5 show a second embodiment of the invention. Spacer of this example In the roller 3b, a partial circle is formed radially outward at one axial end of the inner member 15. A circumferential flange 20 is formed and an angular projection 22 extends tangentially to the other axial end. There are three. This inner member 15 basically has a perfect circular contour and a relatively thick thickness. It has the shape of a solid disk, and its center hole 17 is press-fitted into the shaft 2 of the photosensitive drum. Then, by cutting off a portion of the outer circumferential surface that is closer to the inner circumference than each angular protrusion 22, As shown in phantom lines in FIG. It is designed to be able to transform.

[0015] The outer member 16 is relatively close to the perfect circular contour portion 13 on the outer peripheral surface of the inner member 15. It has a ring shape that can be fitted rotatably without any gaps.

[0016] When assembling the outer member 16 to the inner member 15, each angular projection 22 is The outer member 16 is fitted from this side while being deformed inward. The angular projection 22 is When the external force is released, the free end protrudes outward from the perfect circular contour portion 13, so that each frame The inner member 15 is prevented from coming off by the flange 20 and each angular projection 22.

[0017] In both the first and second embodiments, both the outer and inner members are impregnated with oil. Therefore, due to its self-lubricating property, relative rotation can be performed extremely smoothly. Therefore, the outer member Even when rotating in contact with the toner drum, wear between the outer and inner members is less likely to occur. , can maintain high accuracy over a long period of time.

[0018]

[Effect of the idea]

In this way, according to the present invention, the outer member is fixed to the shaft. Since it can be configured to rotate, it can be mounted relative to each other using a self-lubricating synthetic resin material. A sliding surface can be formed. Therefore, the friction resistance of rotating parts is reduced and wear resistance is improved. This improves accuracy, which has a great effect on maintaining high accuracy over a long period of time. be. In addition to this, an angular shape integrally formed on either the outer or inner member The protrusion prevents the two parts from falling out, so it is especially important to avoid separate parts such as stop rings. It is also effective in simplifying parts management and manufacturing processes. be.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing the main parts of an electronic printer to which a spacer roller according to the present invention is applied.

FIG. 2 is an exploded perspective view showing a first embodiment of a spacer roller.

FIG. 3 is an assembled side view of the first embodiment of the spacer roller.

FIG. 4 is an assembled perspective view with a portion cut away of a second embodiment of the spacer roller.

FIG. 5 is an assembled side view of a second embodiment of a spacer roller.

[Explanation of symbols]

1 Photosensitive drum 2 Axis of photosensitive drum 3 (3a/3b) Spacer roller 4 Toner drum 5.15 Inner parts 6.16 Outer parts 7.17 Center hole 8 Groove 9 Partial annular inner peripheral surface 10/20 Partial circumferential flange 11 Arcuate process 12.22 Angular process 13 Perfect circular contour

Claims (1)

[Scope of utility model registration request] Claim 1: The distance between the axes of the plurality of drums is determined by being rotatably fitted onto the shaft of one of a pair of rotating drums arranged parallel to each other and abutting the outer peripheral surface of the other drum. The inter-shaft spacer is made of a self-lubricating synthetic resin material and includes an inner member integrally coupled to the shaft and rotatably engaged with the inner member. A plurality of protrusions whose free ends can be elastically deformed in the radial direction are integrally formed on either the inner member or the outer member, so that the inner and outer members can be joined together. An inter-shaft spacer characterized in that when the two members are combined, the protrusion engages with one of the other members, thereby preventing relative axial displacement of both members.