KR102240606B1 - CNG engine modified for ready-mixed concrete trucks - Google Patents

Abstract

In a CNG engine, the present invention relates to a CNG engine modified for a ready-mixed concrete truck, comprising: an engine block in which a gearbox is formed at the rear of the CNG engine; a fixed body formed on one side of the engine block and formed with a space therein and a shaft hole in the front center; a driving gear installed in the internal space of the fixed body and connected to a main shaft in the gearbox connected to a cylinder of the CNG engine through a linkage gear to generate a rotational force; a PTO shaft coupled to the driving gear and having a tip protruding to the outside through the shaft hole of the fixed body to generate a driving force while rotating integrally with the driving gear; a bearing block coupled to an end of the fixed body and having a shaft hole formed in the center to support the PTO shaft while passing the PTO shaft; a ring-shaped bearing housing seated in the shaft hole of the bearing block; an elastic pad seated on the entire inner wall surface of the bearing housing, elastically stretched and restored, and elastically deformed when an external force is applied to the PTO shaft in a radial direction to absorb the external force; and a connector having a female connection gear unit corresponding to a male connection gear unit formed on an inner wall to be engaged with the male connection gear unit on the outer periphery of the shaft part of the PTO shaft and engaged with the male connection gear unit to transmit the rotational force while sliding back and forth along the male connection gear unit. Accordingly, the service life of a ready-mixed concrete truck can be substantially extended.

Description

CNG engine modified for ready-mixed concrete trucks}

The present invention relates to a CNG engine, and more particularly, to a CNG engine modified for a ready-mixed concrete truck that can be replaced after removing the diesel engine from a ready-mixed concrete truck using a diesel engine by remodeling the CNG engine.

As the use of fossil fuels increases and the resulting air pollution increases rapidly, the problem of air pollution has become a major concern worldwide. Among the air pollution, the problem of air pollution caused by automobiles is even more serious, and regulations on exhaust gases emitted from automobiles are already tightened. In the case of Korea, the level of emission prevention technology for gasoline vehicles is at the level of advanced countries, but for diesel engines, the level of prevention technology is still inferior to that of advanced countries. The adverse effects of nitrogen oxides and fine dust on the air environment and human body are very large.

Therefore, Korean regulatory authorities are also moving toward restricting the operation of diesel engine vehicles.

Ready-mixed concrete trucks also use diesel engines, but according to government regulations, they can only be operated by installing an emission reduction device, and diesel engines that have been running for a certain period of time are legally prohibited from running at all.

Therefore, the diesel engine installed in the ready-mixed concrete truck must be scrapped despite the fact that other devices can be sufficiently used, except for diesel engines that have exceeded legal standards.

As described above, the diesel engine mounted on the ready-mixed concrete truck can be functionally fully used after the legal use period, but due to environmental regulations, it is inevitable that the vehicle can be scrapped, which is environmentally beneficial, but in other economic aspects, large losses occur.

The CNG engine is a gas stored by compressing natural gas and refers to an engine that compresses and uses city gas used in homes and factories to use it as automobile fuel.

CNG engines are also widely used in buses operated in Korea because of their low exhaust gas and low noise.

Buses operated in Korea have a service life limit determined by regulatory authorities, and even if the CNG engine satisfies the environmental pollution standards sufficiently, it must be discarded after the service life due to the structural stability of the bus.

In the present invention, since the CNG engine is also discarded when the bus is disposed, the CNG engine is separated from the discarded bus that satisfies the environmental pollution standards of the regulatory authorities and replaced with the diesel engine of the ready-mixed concrete truck, thereby substantially reducing the service life of the ready-mixed concrete truck. A device that can be tuned into a low-emission vehicle so that it can be extended was conceived.

Korean Patent Registration No. 10-1728397 Korean Patent Registration No. 10-1189228 Korean Patent Application Publication No. 10-2012-55607 Korean Patent Application Publication No. 10-2013-131785

The present invention is to solve the above-described problems, and it can be sufficiently used functionally, but because of the government's environmental regulations, the entire ready-mixed concrete truck using the diesel engine is not discarded, but only the diesel engine is removed and environmental pollutants are removed. By remodeling the CNG engine, which produces little emission, and installing it on a ready-mixed concrete truck, it intends to legally use a ready-mixed concrete truck, which is restricted to use under environmental regulations, as a low-emission vehicle.

In order to achieve the above object, the present invention provides a CNG engine comprising: an engine block at a portion in which a gearbox is formed at the rear of the CNG engine; A fixed body formed on one side of the engine block, a space formed therein, and a shaft hole formed in a front center; A driving gear installed in the inner space of the fixed body and connected to a main shaft in a gearbox connected to a cylinder of a CNG engine through a linkage gear to generate rotational force; A PTO shaft coupled to the drive gear and protruding to the outside through a shaft hole of the fixed body to generate a driving force while being rotated integrally with the drive gear; A bearing block coupled to an end of the fixed body and having a shaft hole formed at the center thereof to support the PTO shaft while passing the PTO shaft; A ring-shaped bearing housing seated in the shaft hole of the bearing block; An elastic pad that is seated on the entire inner wall surface of the bearing housing, elastically expands and contracts, and is elastically deformed when an external force is applied to the PTO shaft in a radial direction and absorbs the external force; And a female connection gear corresponding to the male connection gear is formed on the inner wall so as to be engaged with the male connection gear on the outer circumference of the shaft of the PTO shaft, and after being meshed with the male connection gear, it is possible to transmit rotational force while sliding back and forth along the male connection gear. It provides a CNG engine modified for a ready-mixed concrete truck, characterized in that consisting of; including a connector.

According to the present invention, if the diesel engine is replaced with a modified CNG engine in a ready-mixed concrete truck equipped with a diesel engine that can be used functionally, but must be discarded because of emission regulation, the stricter emission gas environmental standards of regulatory authorities As it can meet, it is possible to substantially extend the service life of the ready-mixed concrete truck.

In addition, since the PTO shaft of the modified CNG engine protrudes to the outside of the gearbox housing, the external force acting in the radial direction increases when the PTO is connected, so fatigue failure can easily occur in the PTO shaft and bearing parts. By applying an elastic pad, it can absorb the external force in the radial direction elastically, so that fatigue failure of the PTO shaft and bearing part can be prevented in advance.

In addition, if the elastic pad is formed as one, it can easily be deformed by pressure or heat.However, by connecting several urethane wires, it is not easily deformed by heat or pressure, increasing the reliability of the device, and consumable bearings or bearing housings. Since the replacement cycle of the elastic pad can be extended, the maintenance cost of the device is greatly reduced.

1 is an interior view of a gearbox of a modified part of a CNG engine according to the present invention.
Figure 2 shows the appearance of the PTO shaft of the modified part of the CNG engine according to the present invention.
3 is an exploded perspective view of a main part of the modified part of the CNG engine according to the present invention.
Figure 4 is a cross-sectional view of the main part of the modified part of the CNG engine according to the present invention.
5 is an enlarged cross-sectional view showing a coupling relationship between a bearing housing, an elastic pad, and a bearing mounted on a bearing block of a CNG engine according to the present invention.

The present invention will be described with reference to the accompanying drawings as follows.

1 to 5, the present invention removes only the diesel engine from a ready-mixed concrete truck equipped with a diesel engine, and modifies a compressed natural gas engine (CNG engine) used in a bus instead of the diesel engine. And install it.

The ready-mixed concrete truck is equipped with a PTO (Power take off), which is a device that rotates the mixer drum using the driving power of the diesel engine, and the diesel engine for the ready-mixed concrete truck is connected to the PTO using a universal joint to prevent the mixed cement from hardening. It is equipped with a PTO shaft capable of rotating the mixer drum.

However, since CNG engines have not been developed for ready-mixed concrete trucks until now, a separate PTO shaft that can be connected to the PTO in the CNG engine must be provided.

The CNG engine modified in the present invention is mounted on a bus and used, but is used when the bus is disposed of due to the legal age of the bus.

The legal service life of a bus is achieved by comprehensively judging the durability of the bus and other devices, but even if the legal service life of the bus is exhausted, it can sufficiently satisfy the environmental standards of regulatory authorities due to the characteristics of the CNG engine.

As described above, even if the environmental standards of the regulatory authorities can be sufficiently satisfied, most cases are discarded together with the bus due to the legal service life of the bus. Therefore, in the present invention, the CNG engine of the CNG engine is discarded as described above.

In particular, the CNG engine of the bus has similar output to the diesel engine installed on the ready-mixed concrete truck, so it is suitable not only for driving the ready-mixed concrete truck but also for driving the PTO after remodeling.

However, if a separate PTO shaft is provided in the CNG engine and then protruded to the outside of the gearbox housing, the length of the PTO shaft is lengthened. It is often destroyed.

Therefore, in the present invention, a separate PTO shaft connected to the PTO already installed in the truck is provided in the CNG engine, but when a radial external force is applied, the external force is elastically absorbed to prevent fatigue failure of the PTO shaft and the bearing installation part. It is important.

1 is a view showing the inside of the gearbox 120 by separating the gearbox housing 200 at the rear of the CNG engine 100 according to the present invention, and FIG. 3 is an exploded view of the main part according to the present invention. The gearbox 120 is formed at the rear of the engine block 110 of the CNG engine 100. Hereinafter, the tail of the engine block 110 is referred to as an engine block 110.

1 and 3, a main shaft (MS) connected to a cylinder (not shown) of the CNG engine 100 is formed, and a connection gear (CG) that engages and interlocks with the main shaft (MS) on one side The driving gear 140 meshed with the connection gear CG is formed through. The CNG engine 100 for a bus is already equipped with a gear for operating the air compressor so as to operate the brake of the bus, and the gear for operating the air compressor is referred to as a drive gear 140 in the present invention.

A plurality of bolt holes H are formed in the drive gear 140 at regular intervals. The bolt hole (H) is formed so that the PTO shaft to be described later can be coupled to the bolt (B).

A fixed body 130 is formed on one side of the engine block 110. Since the fixed body 130 is formed inside the gearbox housing 200, it is formed to be lower than the depth of the gearbox housing 200. The fixed body 130 forms a shaft hole in the gearbox housing 200 in a state in which the PTO shaft 150 to be described later is coupled, and the PTO shaft 150 protrudes to the outside through the shaft hole. A shaft hole (SH) through which the shaft 150 passes is formed, and at the end of the shaft hole (SH), a plurality of bolt holes (H) are formed at regular intervals along the circumference so that the bearing block 160, which will be described later, can be coupled. have.

The PTO shaft 150 is coupled to the driving gear 140. The PTO shaft 150 is composed of a body 152 and a flange 154), and a flange 154 is formed at the lower end of the body 152, and a bolt hole of the driving gear 140 ( A bolt hole (H) corresponding to H) is formed so that the driving gear 140 and the PTO shaft 150 are coupled using the bolt (B). A male connection gear part 156 meshed with a connector 210 to be described later is formed on the upper outer periphery of the PTO shaft 150. The male connection gear part 156 is made of a plurality of male connection gears 158 formed like rails in the axial direction.

A bearing block 160 is coupled to the outer end of the fixed body 130. A plurality of bolt holes (H) corresponding to the bolt holes (H) of the fixed body 130 are formed in the bearing block 160, so that the bearing block 160 is attached to the fixed body 130 by using the bolts (B). Combine. The bearing block 160 also has a shaft hole (SH) through which the PTO shaft 150 passes, and when the PTO shaft 150 passes through the shaft hole (SH) of the bearing block 160, the body of the PTO shaft 150 ( 152 is designed to be seated on the bearing block 160.

A bearing 170 is inserted between the bearing block 160 and the PTO shaft 150. Three bearings 170 are formed in succession, but forming three bearings 170 in a row without one is very absorbing the external force when an external force vibrating in the radial direction is applied to the PTO shaft 150. Because it serves an important function.

When a continuous external force vibrating in a radial direction is applied to the PTO shaft 150 by a connector 210 connected to a mixer drum (not shown) of a ready-mixed concrete through a universal joint, fatigue failure may occur due to repeated impact force. In addition, the bearing 170 and the bearing block 160 supporting the PTO shaft 150 may also undergo fatigue failure due to an external force.

Although the bearing 170 has a function to smoothly rotate the PTO shaft 150, it should also have a function of preventing fatigue failure from occurring even if the PTO shaft 150 is used for a long time. Even though the bearing 170 is made of one and the width of the bearing 170 is wide, most of the external force applied to the bearing 170 by the PTO shaft 150 is applied to the front end of the bearing 170. Therefore, even if the width of the bearing 170 is wide, most of the external force in the radial direction when the PTO shaft 150 is rotated is applied to the end of the bearing 170, so that the PTO shaft 150 or the bearing 170 and the bearing block 160 It doesn't help much in preventing fatigue failure.

If the bearing 170 is worn or damaged during use, the entire bearing 170 must be replaced. If the bearing 170 is one, the replacement operation becomes complicated and replacement costs are inevitable.

If the bearing 170 is made of three, most of the radial external force by the PTO shaft 150 is applied to the tip, so that only the bearing at the tip end can be replaced even when replacing, and the replacement work is convenient and the replacement cost is inexpensive. In addition, by applying a urethane wire 192 to be described later having different elastic force (elastic restoring force) to the three bearings 170 by an elastic pad 190 to be described later, the PTO shaft 150 and the bearing 170 and the bearing block 160 are applied. ) Can be easily absorbed in the radial direction.

3 and 4, a bearing housing 180 supporting three bearings 170 at once is inserted between the bearing block 160 and the bearing 170, and the inner wall of the bearing housing 180 The elastic pad 190 is inserted. The bearing housing 180 is made of a steel plate, but the elastic pad 190 is made of a hard urethane wire 192. The urethane wire 192 is fine in the nature of the material, but has an elastic force (elastic restoring force), so when an external force in the radial direction vibrating by the PTO shaft 150 is applied to the elastic pad 190, it is instantly contracted and restored to reduce the external force. Absorbs.

In addition, the elastic pad 190 was manufactured by connecting a plurality of urethane wires 192 having a square cross section. If the elastic pad 190 is made into one without connecting a plurality of urethane wires 192, deformation may easily occur. The urethane wire 192 can easily adjust the hardness by changing the composition of the raw material urethane, and the tip of the elastic pad 190 may have relatively high hardness to reduce elastic deformation, and the elastic pad 190 The other side may have a relatively low hardness so that the elastic deformation may be larger. That is, since it is manufactured by connecting several urethane wires 192, it is very easy to increase or decrease the elastic force of a specific part.

As shown in FIGS. 2 and 5, a connector 210 is engaged with the male connection gear 156 of the PTO shaft 150. The connector 210 is connected to the mixer drum of the ready-mixed concrete through a universal joint already provided in the ready-mixed concrete truck-hybrid pump-hybrid motor-reduction gear, and an arm corresponding to the male connection gear 158 on the inner wall of the connector 210 Since the connecting gear 212 is machined, it can be slid in the axial direction in the engaged state. Since it is possible to slide in the axial direction in the engaged state, power can be transmitted while moving back and forth even if there is continuous vibration in the axial direction in the connected state, and the length can be adjusted in the axial direction even when connecting during the power transmission process. It is convenient.

Referring to the operation of the natural gas engine modified for a ready-mixed concrete truck according to the present invention as described above is as follows.

The power transmission to the ready-mixed concrete mixer drum is the main shaft of the gearbox-drive gear-PTO shaft-connector-universal joint-hybrid pump-hybrid motor-reduction gear-mixer drum.

Here, since the process of transferring from the universal joint to the mixer drum is already provided in the ready-mixed concrete truck, the PTO shaft 150 and the bearing 170 generated during the power transfer process and the power transfer process from the main shaft (MS) to the connector 210 ) The effect of the vibrating radial external force generated during the rotation of the PTO shaft 150 at the installation part will be described.

When power is transmitted to the main shaft MS through the cylinder of the CNG engine 100, the power is transmitted to the driving gear 140 through an idle gear. Since an air compressor for brake operation is also connected to the driving gear 140, it is also used for brake operation, and power is transmitted to the PTO shaft 150 through the driving gear 140.

When the PTO shaft 150 is rotated through the drive gear 140, the connector 210 connected to the PTO shaft 150 rotates, and the power is transmitted to the universal joint-hybrid pump-hybrid motor-reduction gear-mixer drum connected thereto. Eventually, the mixer drum rotates.

The external force applied to the PTO shaft 150 by the connector 210 is applied to the male connection gear 156 of the PTO shaft 150. Since the external force applied to the male connection gear unit 156 becomes a force to operate the hybrid pump through the universal joint, a load for operating the hybrid pump is applied to the male connection gear. That is, the load applied to the male connection gear part 156 is much smaller than the force sufficient to fatigue the male connection gear 158.

However, when the connector 210 connected to the PTO shaft 150 is rotated, vibration occurs in the radial direction, so that the PTO shaft 150 continuously collides with the bearing block 160, and not only the PTO shaft 150 but also the PTO shaft 150 ) Can be destroyed by fatigue, but in the present invention, when a radial external force is applied to the PTO shaft 150, the PTO shaft passes through the bearing 170 and passes through the elastic pad 190, but the PTO shaft in the radial direction As 150 is interlocked, it absorbs the impact elastically.

When a radial external force is applied to the elastic pad 190, each elastic urethane wire 192 absorbs the external force by instantaneous contraction and restoration, and the elastic pad 190 has a rectangular cross section. ) Is continuously bonded, so it absorbs external force through elastic contraction and restoration for a long period of time without causing permanent deformation.

100: CNG engine 110: engine block
120: gearbox 130: fixed body
140: drive gear 150: PTO shaft
152: body 154: flange
156: male connection gear 158: male connection gear
160: bearing block 170: bearing
180: bearing housing 190: elastic pad
192: urethane wire 200: gearbox housing
210: connector

Claims (4)

In the CNG engine,
An engine block 110 at the rear of the CNG engine in which the gearbox 120 is formed;
A fixed body 130 formed on one side of the engine block 110, a space formed therein, and a shaft hole formed at a front center;
A drive gear 140 installed in the inner space of the fixed body 130 and connected to the main shaft of the gearbox 120 connected to the CNG engine cylinder through a connection gear to generate rotational force;
A PTO shaft 150 coupled to the driving gear 140 and protruding to the outside through the shaft hole of the fixed body 130 to generate a driving force while being rotated integrally with the driving gear 140;
A bearing block 160 that is coupled to an end of the fixed body 130 and has a shaft hole formed at the center thereof to support the PTO shaft 150 while passing the PTO shaft 150;
A ring-shaped bearing housing 160 seated in the shaft hole of the bearing block 160;
A bearing 170 inserted between the bearing block 160 and the PTO shaft 150 to support the PTO shaft;
An elastic pad that is seated on the entire inner wall surface of the bearing housing 160, elastically expands and contracts, and is elastically deformed when an external force vibrating in a radial direction is applied to the PTO shaft 150 and absorbs the external force ( 190); And
A female connection gear part 212 corresponding to the male connection gear part 156 is formed on the inner wall so that it can be engaged with the male connection gear part 156 on the outer circumference of the shaft part of the PTO shaft 150, and the male connection gear part 156 A connector 210 capable of transmitting rotational force while sliding back and forth along the male connection gear unit 156 after being engaged;
CNG engine modified for a ready-mixed concrete truck, characterized in that made, including. The method of claim 1,
The elastic pad 190 is a CNG engine modified for a ready-mixed concrete truck, characterized in that a plurality of rigid urethane wires 192 having a rectangular cross section are continuously connected. The method of claim 1,
The bearing 170 is a CNG engine modified for a ready-mixed concrete truck, characterized in that consisting of three. The method of claim 1,
The plurality of urethane wires 192 constituting the elastic pad 190 are characterized in that the elastic strength of each urethane wire 192 is made differently so that a specific part can have higher or lower elastic strength than other parts. CNG engine modified for ready-mixed concrete trucks.

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